Niger: a timeline of abductions and killings

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.

- January 22, 2009: Four European tourists, including two Swiss, one German woman and a Briton, are captured in the border zone between Mali and Niger. In June AQIM claims to have for the first time killed a western hostage, the Briton Edwin Dyer. The three others are freed in April and July.

- December 30, 2009 and January 1, 2010: Seven soldiers and their civilian guard are killed during attacks by heavily armed men in the village of Tlemss, on the border with Mali. Three of the attackers are killed by the army.

- March 9, 2010: The Niger government confirms the death of five soldiers and three attackers in a violent assault a day earlier on a military post in western Niger. According to an anonymous Malian security source and a Malian parliamentarian, the attack was carried out by AQIM.

- April 20, 2010: A French national is abducted in Niger in the border region with Mali and Algeria. He is then transferred to Mali. A Franco-Mauritanian raid carried out on July 22 to try to liberate him -- during which seven members of AQIM are killed -- fails. On the 25th, AQIM claims the execution of the man, Michel Germaneau.

- September 16, 2010: Seven people -- five French, one Togolese and one Madagascan, working for the French nuclear group Areva and its subcontractor Satom -- are abducted at Arlit, a uranium mining zone in the north of the country. AQIM claims the kidnappings. A French woman who is ill and the hostages from Madagascar and Togo are released on February 24, 2011. The four other French hostages remain in AQIM's hands.

- January 7, 2011: Two young Frenchmen, Antoine De Leocour and Vincent Delory, are abducted in central Niamey. They are killed a day later during a Franco-Nigerian bid to rescue them on Malian territory. On the 13th, AQIM claims the abduction.

- October 14, 2012: Six humanitarian workers -- five from Niger and one from Chad -- are kidnapped in northern Niger, in the border area with Nigeria. They are taken to the north and then to neighbouring Mali. On November 3 the aid workers from Niger are freed, but their Chadian companion dies of his injuries. According to a former hostage, the Islamist group the Movement for Oneness and Jihad in West Africa (MUJAO) is behind the abduction, information confirmed by a Niamey official.

- May 23, 2013: Islamist militants stage twin suicide car bombings on an army base and a French-run uranium mine in Niger, killing at least 20 people and taking several trainee officers hostage. The attack is claimed by MUJAO as revenge for Niger's involvement in a French-led military offensive in Mali.