A Bangladeshi lawyer who fought for the state in a high-profile murder trial against Islamist extremists has disappeared, the police said on Sunday. Ratish Chandra Bhowmik has not been seen since Friday, when he left his home in Rangpur, AFP reported.

Bhowmick’s family reported his disappearance after he did not return home and his mobile phone was found switched off, PTI reported.

Just weeks earlier, Bhowmick led the case against seven militants from the Jamayetul Mujahideen Bangladesh for murdering the caretaker of a Sufi shrine in November 2015. The seven men were sentenced to death, and nearly a dozen others from the homegrown extremist group were convicted for the murder, according to AFP.

Bhowmik was also the main prosecutor in another case against five JMB extremists, who were sentenced to death for the murder of a Japanese farmer in 2015. He also served as a crucial witness to the trial of a Jamaate-Islami leader, Azharul Islam, who was sentenced to death by a special tribunal for committing crimes against humanity with Pakistani troops during Bangladesh’s 1971 liberation war, according to PTI.

Rangpur regional police chief Khandaker Golam Faruque told AFP on Sunday that Bhowmik had refused an armed escort during the high-profile trials. “We have launched a coordinated campaign to trace him,” Faruque said.

Bangladesh’s elite anti-crime Rapid Action Battalion and intelligence agencies are working to find the lawyer.

The government has been cracking down against the Jamayetul Mujahideen Bangladesh, which has been blamed for several attacks on religious minorities, atheist bloggers and foreigners in the past few years.

In July 2016, suspected JMB terrorists attacked a cafe in Dhaka and killed 22 hostages, including 18 foreigners – an assault claimed by the Islamic State group. Security forces have tracked and killed more than 70 alleged terrorists since, while hundreds of others have been arrested and sentenced to death for other terror attacks, PTI reported.