Top Mumbai police officer Himanshu Roy committed suicide at his residence on Friday, The Times of India reported. Roy, the additional director general of police (Establishment), was suffering from cancer, according to News 18.

An Indian Police Service officer of the 1988 batch, Roy held a number of important posts throughout his career. He used to head the Maharashtra Anti-Terrorism Squad, or ATS, before being transferred in 2015. During his tenure, the ATS arrested software engineer Anees Ansari for allegedly planning to blow up the American School in Mumbai’s Bandra Kurla Complex.

Roy also led the high-profile investigation into the Indian Premier League betting scandal in 2013. At that time he was the joint commissioner of the crime branch. He also investigated the murder cases of Pallavi Purkayastha and journalist J Dey.

Roy had seven years of service left. “He was a very bright officer,” MN Singh, who was once Roy’s superior, told NDTV. “Such a tragedy.” His colleague, Arup Patnaik, said Roy was a fitness freak. “He was at an advanced stage of cancer and couldn’t take it anymore. It is very, very unfortunate,” he told the news channel.