JUDGMENT : S.P. SINGH & S. ALI AHMAD, JJ. 1. This application under Article 226 of the Constitution of India has been filed by the petitioners for issue of a writ quashing ORDER :s contained in Annexure 7, 8, 9 and directing the respondents not to reduce the petitioners in rank to interfere with their rights in any way. Annexure 7 contains an ORDER :dated 22.5.1973, declaring null and void confirmation of Assistant Sub Inspectors, Paramhans Narain Singh (petitioner no. 2) and Nazir Ahmad Khan (petitioner no. 1). Annexure 8 contains another ORDER :of the same date reverting the three petitioners to the rank of 'Head Rakshaks' in the scale of Rs. 80-110/- from the rank of officiating Assistant Sub Inspectors in the scale of Rs. 110-170/-. Annexure 9 also contains an ORDER :of the same date, i.e. 22.5.1973, promoting the three petitioners to officiate as Assistant Sub Inspectors in the scale of Rs. 110-170/- with effect from 23.5.1973. 2. The case of the petitioners, as made out in the petition, is that petitioners no. 1 and 2, Nazir Ahmad Khan and Paramhans Narain Singh, were placed provisionally on the panel for promotion from the rank of 'Head Rakshaks/Uniform Branch in the scale of Rs. 80-110/- to the rank of Assistant Sub Inspectors/Uniform Branch in the scale of Rs. 110-170/- as a result of selection Board held on 25-26th April, 1968 at Muzaffarpur (copy of this office ORDER :has been made Annexure 1 to the petition). By office ORDER :dated 13.5.1968, petitioner no. 1 and 2 were temporarily promoted to the posts of Assistant Sub Inspector/Uniform Branch (copy of this ORDER :has been made Annexure 2 to the writ petition). By another office ORDER :dated 28.3.1969, petitioner no. 3, Sheoji Singh was allowed to officiate as an Assistant Sub Inspector/Uniform Branch with effect from 27.2.1969 (copy of this ORDER :has been made Annexure 3 to the writ petition). By office ORDER :dated 10.4.1969, the three petitioners were placed finally for promotion to the rank of Assistant Sub Inspectors (copy of this ORDER :has been made Annexure 4 to the writ application). By office ORDER :dated 3.6.1969, petitioner no. 3 was posted permanently against the existing vacancy of Assistant Sub Inspector at Garhara with immediate effect (copy of this ORDER :has been made Annexure 5 to the writ application). By another office ORDER :dated 13.12.1970, petitioner no. By office ORDER :dated 3.6.1969, petitioner no. 3 was posted permanently against the existing vacancy of Assistant Sub Inspector at Garhara with immediate effect (copy of this ORDER :has been made Annexure 5 to the writ application). By another office ORDER :dated 13.12.1970, petitioner no. 1 and 2 were confirmed as Assistant Sub Inspector (copy of this ORDER :has been made Annexure 6 to the writ petition). The grievance of the petitioner is that they having been confirmed as Assistant Sub Inspectors, have been illegally reverted to the posts of 'Head Rakshaks' when there was nothing against them and they were not called upon to show cause against any charge. 3. A counter affidavit has been filed on behalf of the respondents in which it has been, inter-alias, alleged that the petitioners were promoted to the rank of Assistant Sub Inspectors in contravention of Regulation 10 of Chapter XII of the Railway Protection Force Regulations 1966, and, therefore, their promotion was ultra vires. It is, therefore, claimed by the respondents that the petitioners were not entitled to any notice for correcting the mistake and no illegality has been committed in reverting them to the rank of 'Head Rakshaks' which they were holding originally and appointing them to the post of Assistant Sub Inspectors on officiating basis. 4. Annexure 6 clearly shows that petitioner no. 1 and 2, namely, Nazir Ahmad Khan and Paramhans Narain Singh, were confirmed to the post of Assistant Sub Inspectors in the scale of Rs. 110-170/- in Uniform Branch with effect from 1.4.1970. There was some controversy at the bar on the question whether petitioner no. 3, Sheoji Singh, has been confirmed in the rank of Assistant Sub Inspector or not. In paragraph 17 of the counter-affidavit filed on behalf of the respondents, it is stated that in view of the fact that the petitioners were promoted and confirmed as Assistant Sub Inspectors on the basis of an illegal selection, the provisions of Section 9 of the Railway Protection Force Act, 1957 or Article 311 of the Constitution of India were not applicable and that there has been no violation of the principles of natural justice. Learned counsel for the petitioners has submitted that in this paragraph, the respondents have admitted that all the three petitioners have been confirmed. Learned counsel for the petitioners has submitted that in this paragraph, the respondents have admitted that all the three petitioners have been confirmed. Apart from what is stated in paragraph 17 of the counter affidavit, Annexure 8 shows that petitioner no. 3 was also reverted from the rank of Assistant Sub Inspector to the rank of 'Head Rakshak' and Annexure 9 shows that he was again promoted to officiate as Assistant Sub Inspector. Had petitioner no. 3, Sheoji Singh, been not confirmed, there would have been no necessity for passing such ORDER :s reverting him to the rank of 'Head Rakshak' and again promoting him to the rank of Assistant Sub Inspector on officiating basis. Therefore, on the materials available on record, we will proceed on the assumption that respondent no. 3, Sheoji Singh, was also confirmed as Assistant Sub Inspector. 5. We now take up for consideration the main question arising for decision in the case whether any illegality has been committed in reverting the petitioners to the post of 'Head Rakshaks' without calling upon them to show cause against such revertion. In this connection, reliance has been placed by learned counsel for the respondents on Regulations 10 of Chapter XXII of the Railway Protection Force Regulations, 1966. These regulations were made by Inspector General contained under Rule 32 of the Railway Protection Force Rules, 1959. Regulation 10 runs as follows:– Promotion of Head Rakshaks in the grade of Assistant Sub Inspector:– "(i) Promotion to the grade of Assistant Sub Inspector shall be made by the Security Officer concerned on the basis of selection held centrally once in 2 years and oftener if necessary. The number of candidates to be called from the region, Divisions shall be determined by the Chief Security Officer having due regard to the existing and anticipated vacancies and the number of men required for panel and shall not normally exceed 4 times the number to be empanelled. (ii) All head rakshaks who have satisfactorily completed their two years probation as Head Rakshaks, shall be eligible to be called for selection according to their seniority in the branch concerned. Thereafter, the Chief Security Officer will constitute a Selection committee consisting of two security officers and one Assistant Security Officer. This committee shall hold written and/or oral tests at the head quarters of the Security Officer concerned. Thereafter, the Chief Security Officer will constitute a Selection committee consisting of two security officers and one Assistant Security Officer. This committee shall hold written and/or oral tests at the head quarters of the Security Officer concerned. Selection will be made primarily on the basis of overall merit, but for the guidance of the selection committee the same procedure as laid down in para 5 above will be followed. (iii) Those who are declared suitable by the selection committee will then be placed on a list according to their relative seniority as Head Rakshaks but those securing a total of more than 75% marks will be classed as 'outstanding' and will be placed on the top of the list in the ORDER :of their seniority. The list shall be submitted to the Chief Security Officer for his approval. After approval this list shall be maintained by the Security Officer concerned who will issue ORDER :s of promotion to the rank of Assistant Sub Inspector accordingly." Learned counsel for the respondents has strongly relied on the expression 'centrally' in Clause (i) of the said Regulation and has submitted that selection of the petitioners was not made centrally as required by the regulation, but on zonal basis and, therefore, the selection was illegal. It may be stated here that the petitioners belonged to North Eastern Railway, which has got two zones, Eastern Zone with headquarters at Muzaffarpur and Western Zone with headquarters at Lucknow. Each zone has got two divisions. The headquarters of the two divisions in Eastern Zone are situate at Varanasi and Samastipur, whereas the headquarters of the two divisions in the Western Zone are situate at Lucknow and Ijat Nagar. The petitioners belonged to the eastern zone and their selection was held at Muzaffarpur. On the other hand, learned counsel for the petitioners has submitted the expression 'centrally' in clause (i) of the said regulation does not refer to the North Eastern Railways as a whole but it refers to the zones separately and what is required by clause (i) is that selection for eastern zone is to be made centrally at Muzaffarpur whereas selection for western zone is to be made centrally at Lucknow. In support of this contention, he has placed reliance on the sentence "this committee shall hold written/or oral test at the headquarters of the Security Officer concerned" in clause (ii) of the said regulation. In support of this contention, he has placed reliance on the sentence "this committee shall hold written/or oral test at the headquarters of the Security Officer concerned" in clause (ii) of the said regulation. The Selection committee is to be constituted of two Security Officers of the two Zones and one Assistant Security Officer. Appointments are also to be made by the Security Officer concerned. Learned counsel for the petitioners has, therefore, submitted that since the tests are to be held at the headquarters of the Security Officer concerned, it is manifest that selection for appointment is to be made for the two zones separately and not for the entire railway. We do not consider it necessary to decide categorically which, of the two views as to the interpretation of this regulation is correct. There cannot be any doubt that there is ambiguity in the rules and much can be said in support of both the contentions. Really the selection of the petitioners for promotion to the rank of Assistant Sub Inspector was made at Muzaffarpur accepting the interpretation given to the regulation as is now contended by learned counsel for the petitioners. It is obvious therefrom that even the railway authority gave that interpretation to the regulation at one time. If a regulation is ambiguous and capable of two interpretations, something done on the basis of one interpretation cannot be held to be illegal and ultra vires. We are, accordingly, of the opinion that selection of the petitioners for promotion to the rank of Assistant Sub Inspectors and their subsequent confirmation cannot be held to be ultra vires as contended by learned counsel for the respondents. In that view of the matter, they could not be reverted to the posts of Head Rakshak without giving them an opportunity to show cause. The ORDER :s reverting them to the posts of Head Rakshak is, therefore, to be quashed. 6. In the result, the application is allowed and ORDER :s as contained in Annexure 7, 8 and 9 of dated 22.5.1973, are quashed. In the circumstances of this case, there will be no ORDER :as to costs. Application allowed.