• The leader of Thowheeth Jama'ath, Mohammed Zaharan, is a well-known extremist who has spent time both in India and Sri Lanka and has preached hateful messages online in recent years.
• The Sri Lankan government has confirmed this more than ten days before the attacks, a foreign intelligence agency warned the country's security officials against a potential threat to the churches by Thowheeth Jama'ath.
• The country's security agencies have not responded aggressively to the warnings, calling it a "colossal failure of the intelligence services" and triggering a crisis for the government.
• A forensic analysis of body parts revealed that most attacks were carried out by single bombers, but that two men had attacked the Shangri-La Hotel in Colombo.
• One of the suicide bombers was arrested a few months ago on suspicion of rape of a Buddha statue, a highly provocative act in Sri Lanka, a Buddhist island nation in the Indian Ocean.
• In Washington, intelligence and terrorism researchers investigated possible links between the Islamic state and the attackers, but had not yet reached their final conclusions on Monday afternoon.
What do we know about who was killed and where
• The attacks took place on Sunday morning in three churches and three hotels in three different cities across the island. Two more explosions occurred in the afternoon in and around Colombo, one in a small guest house and the other in the seemingly safe house of the suspects. In this explosion, three officers were killed in search of the attackers.
• The deadliest explosion appeared to be in St. Sebastian's Church in Negombo, about 20 miles north of Colombo, where at least 104 people were killed.
At least 28 people were killed in the Zion Church in Batticaloa on the other side of the island on the East Coast. The shrine of St. Anthony, a Roman Catholic church in Colombo, was also attacked with an unknown number of dead. Witnesses described there a "flow of blood".
• In addition to the Shangri-La, the Cinnamon Grand and Kingsbury hotels, also in Colombo, were also attacked.
• At least 36 of the dead (19459008) were foreigners, including several Americans, the authorities said. Others were British, Chinese, Dutch, Indian, Portuguese, Japanese and Turkish citizens according to official figures and news.
What We Do not Know about the Attacks
. • How a small, obscure group, known primarily for the desecration of Buddhist statues, made skillful, coordinated attacks.
• Which international terrorist network or networks, if any, helped with the attacks.
• The names of the suicide bombers and the 24 people detained in connection with the attacks.
• Why do Catholics appear to be selected by bomb attack in a Buddhist majority with an assassination significant Hindu minority.
• Why the authorities have failed to take significant steps to prevent an attack after receiving reports of an imminent threat.
• What effect does the failure to stop the attacks have on the Government of Sri Lanka. where the President and the Prime Minister were already involved in a bitter feud.
• How many of the approximately 500 injured were in critical condition and what the final death toll might look like.