The Madhya Pradesh Police ordered an inquiry on Sunday after reports said that candidates appearing for the constable’s post were labelled with their castes on their chests during a medical examination in Dhar district, ANI reported.

Photos had emerged in the media on Saturday, showing candidates bare-chested with markings such as “SC”, “ST” and “O” – Scheduled Castes, Scheduled Tribes and Other Backward Classes – in black on their bodies.

Birendra Singh, the superintendent of police of Dhar, condemned the incident and called it “deplorable”. “We have taken the matter seriously as this is wrong and should not happen,” he said. “I have directed an investigation into the matter so that we can prosecute the ones responsible at the earliest.”

He told The Indian Express that examinations officials “must have done it for convenience because the number of constables was very high”.

Director General of Police Rishi Kumar Shukla said candidates should not have been labelled in such a manner. However, he added that there was no bad intention behind the move.

“It was done as a precautionary measure to ensure that there was transparency in the laid down norms for physical measurements of these categories,” Shukla told the Hindustan Times. “I have given instructions to the district police to remove the marking, if any, and to ensure there is no recurrence.”

Criteria for clearing the medical examination, such as height and chest measurements, vary for different categories of candidates.

Civil surgeon Dr Sushil Kumar Khare, who is heading the medical board conducting the examination, said the health department was not involved in the labelling.

“We conduct medical examination of the candidates who are sent by the police department,” he told the Hindustan Times. “I pointed out when I saw ‘O’ written on the chest of a candidate. I was told by the police personnel that ‘O’ denoted ‘OBC’. I think it was done by the police department to identify the candidates from different sections and avoid mixing up of the candidates.”