Sumit Bajaj, one of the three sentenced to 10 years' rigorous imprisonment in the Park Street gang-rape case, moved the high court on Wednesday challenging the trial court's order.

With the appeal, Bajaj also filed an application for bail.

"The appeal will be heard later but the bail petition will be heard soon," Kallol Mondal, the convict's lawyer, said.

The city sessions court had on December 10 pronounced Bajaj and two other accused, Naser Khan and Ruman Khan, guilty of gang-raping a woman on the night of February 5, 2012. The mother of two was raped in a moving vehicle after she had left a Park Street night club.

The trio were sentenced to 10 years' imprisonment - the minimum punishment for the charges slapped on them.

Special public prosecutor Sarbani Roy, in her last submission in the case, had said the three were not the prime accused and were not directly involved in the commission of the offence. Hence, she had submitted, she would not seek punishment higher than the minimum punishment of 10 years in jail.

Roy has since been removed from the post for making the statement.

Weeks after the verdict, Calcutta police moved the high court seeking harsher punishment for the trio. The plea is yet to be heard.

Sources said the other two convicts - Naser and Ruman - would take cue from Bajaj and file similar petitions against the trial court verdict. The trio have been in jail since February 2012.

The prime accused in the case, Kadir Khan, and another accused, Ali, are still at large despite red-corner notices against them.