Sri Lanka President Maithripala Sirisena said Friday morning that security officials are searching for 140 people they believe have links to ISIS and helped carry out the deadly Easter Sunday suicide bombings, The Guardian reports. The president also confirmed that the ringleader of the attacks, Mohammed Zahran, died in the Shangri-La hotel. Authorities are warning Muslims to avoid Friday prayer services out of fear of retaliation attacks, which many of the devout defied. Sirisena said that while counterterrorism officials now say they knew many young people have been increasingly involved with the terror group since 2013, they had not shared that intelligence with him. Authorities have been criticized for ignoring blatant threats about terrorist attacks in churches. At least 253 people died in coordinated attacks on churches and tourist hotels. The death toll was lowered by nearly 100 on Thursday after DNA tests proved that many of the body parts found at the scenes belonged to the same people.