Below is a timeline of the main attacks linked to Islamist militants in Niger over the past five years, after twin car bomb attacks on Thursday in the north of the west African country killed more than 20. - December 14, 2008: Two Canadian diplomats, including the UN secretary general's special envoy, are abducted with their local driver some 40 kilometres (25 miles) to the west of Niamey. The abduction is claimed by Al-Qaeda in the Islamic Maghreb (AQIM), which signs off on its first attack there. The two hostages are freed in Mali in April 2009.

PESHAWAR, Pakistan (Reuters) - The Pakistani Taliban claimed responsibility on Thursday for a bomb that killed 11 security personnel and two civilians in the southwestern city of Quetta. Sixteen people were wounded in the attack in the capital of Baluchistan province, and the death toll could rise, police said. The bomb was planted in a three-wheeled auto-rickshaw and blew up as a truck carrying the security men passed by.

Boston bombing suspect Dzhokhar Tsarnaev wrote a note before his capture in which he called the victims "collateral damage" for US action in Afghanistan and Iraq, local media reported Thursday. "When you attack one Muslim, you attack all Muslims," Tsarnaev also scribbled on the inside wall of the boat where he hid from police during a massive manhunt in the days after the April 15 blasts, according to CBS News. The twin explosions near the finish line of the Boston Marathon killed three people and wounded more than 260.

A provincial high court on Thursday upheld the right of Pakistan to shoot down CIA drones that have killed more than 1,400 civilians in the North and South Waziristan tribal areas in the last five years. "The drone strikes in Pakistan are a blatant breach of the absolute right to life" and "naked aggression on the sovereign territory/airspace of Pakistan...carried out at the whim and will of the CIA," Peshawar High Court Chief Justice Dost Mohammad said in a ruling.