The United States said Monday it was increasing its reward for information about key leaders of Somalia’s Al-Shabaab to $10 million, a move that follows a spate of deadly attacks by the jihadist group. The US State Department also said it was for the first time offering a reward of up to $10 million for information “leading to the disruption of the financial mechanisms” of the Al-Qaeda affiliate. Al-Shabaab militants have stepped up attacks in the Somali capital Mogadishu and other parts of the country in the face of a widescale offensive against the group by the new government of President Hassan Sheikh Mohamud. The US said it was offering up to $10 million for information leading to the identification of Al-Shabaab “emir” Ahmed Diriye, second-in-command Mahad Karate and Jehad Mostafa, a US citizen who it said had various roles in the group. The State Department designated Al-Shabaab as a foreign terrorist organisation in March 2008. The UN’s human rights chief Volker Turk earlier Monday said that more than 600 civilians had been killed this year in attacks by the group in the fragile Horn of Africa nation. In the deadliest attack in five years, twin bombings on October 29 claimed by Al-Shabaab killed at least 121 people and injured 333 others in Mogadishu, the UN said, citing Somali figures. The insurgents have been seeking to overthrow the fragile foreign-backed government in Mogadishu for about 15 years.