The United States said Monday it was increasing its reward for information about key leaders of Somalia’s Al-Shabaab to $10 million apiece, 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 fighters 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 each 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.

“These key leaders of Al-Shabaab are responsible for numerous terrorist attacks in Somalia, Kenya and neighbouring countries that have killed thousands of people,” said a poster issued by the US with pictures of the three men.

UN human rights chief Volker Turk said earlier Monday that more than 600 civilians had been killed this year in attacks largely attributed to the group.

At least 613 civilians have been killed and 948 injured so far in 2022, according to the latest United Nations figures — the highest since 2017 and a more-than 30-percent rise from last year.

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.