Sri Lankan police are on high alert amid fresh bomb scares in the wake of Easter Sunday attacks that killed 359 people and injured more than 500 others. Overnight, authorities arrested 16 more suspects in the case. Among those arrested so far is Mohammad Yusuf Ibrahim, one of Sri Lanka’s richest spice traders. Authorities say two of his sons were among eight suicide bombers who died in Sunday’s attacks. On Wednesday, Sri Lanka’s president sacked the country’s police chief and defense secretary amid widespread reports that security forces had ample warnings about imminent attacks ahead of the bombings, but failed to act.