Friday's attack on a mosque in Egypt's Sinai, which killed at least 235 people, is among the deadliest since the September 11, 2001 attacks on the United States.
US in 2001: nearly 3,000 dead
The deadliest attacks in history take place in the United States on September 11, 2001.
Four passenger aircraft are diverted and three deliberately slammed into the twin towers of the World Trade Center in New York and the Pentagon in Washington DC. The fourth crashes in Pennsylvania.
The attacks are claimed by Al-Qaeda and leave around 3,000 people dead.
Iraq in 2007: 400 dead
On August 14, 2007 four suicide truck bombs explode in the villages of Al-Khataniyah and Al-Adnaniyah, which are mainly inhabited by members of the Yazidi community in Iraq's northern province of Nineveh.
The simultaneous attacks, blamed on Sunni Islamists, leave more than 400 dead.
Somalia in 2017: 358 dead
A truck bomb in a busy commercial district in northwestern Mogadishu leaves 358 dead in Somalia on October 14, 2017, in what is one of the deadliest ever attacks using vehicles as a weapon.
No one claims responsibility, but it is widely seen as being the work of the Shabaab, an insurgent Islamist group aligned with Al-Qaeda.
Iraq in 2016: 323 dead
On July 3, 2016 an explosives-packed minibus blows up, killing 323 people in a packed street in central Baghdad. The attack is claimed by the jihadist Islamic State group.
The enormous explosion, which sets fire to several buildings and single-storey houses, happens in Karrada, a mainly Shiite shopping area in the capital which is crowded before the celebrations of the end of the fasting month of Ramadan.
Egypt in 2015: 224 dead
On October 31, 2015 a Russian jet leaving Egypt crashes in the Sinai peninsula, leaving all 224 people on board dead in Russia's worst air disaster. An Islamic State-linked group claims responsibility for bringing down the plane. Experts do not rule out the possibility of a bomb on board.
Indonesia in 2002: 202 dead
On October 12, 2002 attacks on a bar-restaurant and a discotheque on the island of Bali leave 202 dead, mainly tourists. The attack is carried out by a Jemaah Islamiyah commando linked to Al-Qaeda.