NEW DELHI (AP) — Police in southern India detained a man for suspected involvement in setting off explosives at a Jehovah’s Witness gathering in southern India that killed at least three people and wounded 50 others, authorities said Monday.

Hundreds of faithful were at a prayer session Sunday at the Zamra International Convention Center in the town of Kalamassery in Kerala state when the explosion took place. The state’s top police officer, Sheik Darvesh Saheb, said an initial investigation determined an improvised explosive device was used.

The suspect was identified by police as Dominic Martin, who posted a video on Facebook claiming responsibility for the blast before surrendering to the police. Martin said in the video he feels the Jehovah’s Witness theology is wrong and that is what led him to carry out the blast.

“They teach that all people of the world would perish and only they will live. What should we do with people who long for the ruin of the entire people in the world. I could not find a solution. I took the decision realizing that this idea is dangerous to the country,” Martin said in the video.

Police said they were working to verify Martin’s claims.

Jehovah’s Witnesses identify as Christians but are guided by distinctive beliefs and practices. They are known for their door-to-door proselytism.