In CCTV footage that has recently emerged, a suspected suicide bomber is seen entering St. Sebastian's Church in Negombo minutes before an explosion.
According to a police spokesman, the number of people killed in a series of deadly attacks in Sri Lanka has risen to 310.
After the explosions, authorities launched a massive security operation. As of Monday, at least 24 people were detained in connection with the attacks. The authorities introduced and re-introduced curfew and deployed 1,000 extra troops in Colombo.