The most recent U. S. troops were sent to help set up a new air base, from which to conduct surveillance against Al Qaeda. 40 U. S. Air Force logistics specialists, intelligence analysts and security officers arrived in the capital of Niger on 20 February 2013, bringing the total Americans deployed in Niger to 100. On 24 February 28 Islamists and ten Chadian soldiers were killed while fighting in the Adrar des Ifoghas mountains in Northern Mali. On 26 February, a car bomb exploded in Kidal targeting a MNLA checkpoint. At least 7 MNLA fighters along with the suicide bomber were killed in the attack. On 20 March, AQIM claimed to have executed a French hostage in Mali, Phillipe Verdon, who had been kidnapped in 2011. On 23 March, Islamist fighters from MUJAO attacked the city of Gao, causing heavy fighting for two hours. The Malian army eventually repulsed this attack. On 30 March, a suicide bomber detonated his explosives near a Malian army checkpoint in Timbuktu, allowing a group of jihadists to infiltrate by night. By 1 April, with the help of a French army detachment supported by war jets, the Malian army pushed the jihadists out of the city center. On 29 April, a French paratrooper was killed by a roadside bomb in Northern Mali, the sixth French soldier to die in the conflict. Two others were seriously injured. On 28 February, Algerian television informed that Abdelhamid Abou Zeid, one of the three top men of AQIM and deemed responsible of several kidnappings of westerners in the Sahel in the 2000s, had been killed in battle against Franco-Chadian forces in the Tigharghar mountains along with about 40 of his followers, some kilometres away from Aguelhok. The information was neither confirmed nor denied by the French Army. On 2 March 2013, it was reported that Mokhtar Belmokhtar, mastermind of the In Amenas hostage crisis in which 800 hostages had been taken and 39 Westerners killed at an Algerian oil refinery, had been killed as well. Chadian state television announced that "Chadian forces in Mali completely destroyed the main jihadist base in the Adrar de Ifhogas mountains... killing several terrorists including leader Mokhtar Belmokhtar", according to a BBC report. BBC correspondent Thomas Fessy said this would be a major blow if confirmed. On 4 March 2013, Al Qaeda's North African branch confirmed the death of Abou Zeid, but denied that Belmokhtar had been killed.