An Indonesian forensic policeman take of evidence of a blast at National Monument (Monas) complex in Jakarta, December 3, 2019. Indonesian police cleared a blast site at Indonesia's National Monument park, near the presidential palace in central Jakarta on Tuesday (December 3) after a suspected smoke grenade explosion that injured at least two military officials. ANTARA

An Indonesian forensic policeman take of evidence of a blast at National Monument (Monas) complex in Jakarta, December 3, 2019. The park explosion was suspected to have been caused by a smoke grenade, and two injured military officials had been taken to hospital. ANTARA

An Indonesian forensic policeman takes of evidence of a blast at National Monument (Monas) complex in Jakarta, December 3, 2019. The two injured officers were doing exercises in the park at the time. ANTARA

An Indonesian forensic policeman takes pictures of evidence of a blast at National Monument (Monas) complex in Jakarta, Indonesia, December 3, 2019. The explosion, at 7:15 a.m.(0015 GMT) on the north side of the park, was thought to have been caused by a smoke grenade. ANTARA

A cat is seen next to the evidence of a blast at National Monument (Monas) complex in Jakarta, December 3, 2019. REUTERS/Willy Kurniawan

Armed police officers stand guard following a blast at National Monument (Monas) complex in Jakarta, December 3, 2019. ANTARA