Four people were killed and eight injured in Indonesia on Tuesday after a policeman accidentally detonated a grenade during a security workshop at a local university.

Brigadier Haidir of the Southeast Sulawesi Police Mobile Brigade pulled out the grenade’s pin during a demonstration for security officers at the university in the city of Kendari, according to the Jakarta Post.

He was showing the pin to participants when the grenade exploded. Haidir and three members of the university’s staff were killed by the blast, while Adjunct First Inspector Syafrudin of the police force’s bomb-disposal unit, who was conducting the talk, was injured along with seven others.

Brigadier General Agung Sabar Santoso, the Southeast Sulawesi Police chief, was quoted as saying by the Post that an investigation into the cause of the blast is still in progress.

[Jakarta Post]

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Write to Rishi Iyengar at rishi.iyengar@timeasia.com.