Iraq’s Central Criminal Court sentenced Sunday a prominent Islamic State chemical warfare developer to death, convicting him of developing some of the group’s deadliest weapons.

In a statement on Sunday, Abdul-Sattar Beraqdar, a spokesman of the Supreme Judicial Council, said Zeyad Tarek, who hd joined militant activity in 2003, was sentenced to death based on the Iraqi counter-terrorism law.

He said the convict had confessed to developing toxic weapons for the Islamic State, and had admitted using a chicken coop he owned for the purpose of manufacturing the weapons.

Iraq’s Supreme Judicial Council had previously published an interview with Tarek, in which it revealed that the convict was arrested in Lebanon after an intelligence operation that succeeded in retaking him back to Iraq. He was ambushed outside an embassy in Lebanon where he was applying for asylum.

Tarek, who the militants had nicknamed the “chemicals emir”, said that one of the rockets he had developed could fire for a 20-kilometer range. The council’s paper said several militants arrested for manufacturing chemical weapons and booby-traps had pointed during interrogations to Tarek’s facility.

Iraqi and international agencies had occasionally reported suspected chemical attacks by IS militants during the government’s U.S.-backed military campaign against the group in Mosul, its former capital which Iraqi forces recaptured early July. Source.