Ex-Mumbai top cop Param Bir Singh - who faces four cases of extortion in Maharashtra and had been missing since October, leading to rumours he had fled the country - appeared at the Crime Branch office on Thursday morning.
"I will join the investigation as directed by the court," Mr Singh told reporters as he arrived at Mumbai airport earlier today, after flying in from Chandigarh.
On Monday, the former Mumbai Police Commissioner's lawyer told the Supreme Court his client is "not absconding and is in India. Mr Singh was then granted protection from arrest and asked by the court to join investigations into extortion charges against him.
Mr Singh's lawyer had argued the ex-top cop can "get out of the hole" if he is "allowed to breathe", and that his client faced 'a threat from Mumbai Police" from the moment he lands in Maharashtra.
Param Bir Singh has not reported to work since May - when he was transferred out as Mumbai Police Commissioner and subsequently accused then Maharashtra Home Minister Anil Deshmukh of corruption; Mr Deshmukh has since been arrested and is now in Enforcement Directorate custody.
Mumbai Police had told the court it had no idea where he was.
On November 17, a Mumbai court said Mr Singh could be declared an "absconder", which means he could be treated as a fugitive from the law.