Islamic militants who are on Washington's list of terror groups have cut off the hand of a man convicted of stealing fishing nets, officials said Wednesday.

The Islamic group, al-Shabab, is imposing a strict form of Islam with punishments including lashings and stonings that have drawn fear and trepidation in this Muslim country. In one case, the group stoned a 13-year-old girl to death for adultery even though her parents said she was a rape victim.

Mohamed Sahal Iidle, a judge in the port town of Kismayo, said Wednesday that a 26-year-old man had his hand cut off late Tuesday for stealing three sacks full of fishing nets worth $300 from a businesswoman.

"He screamed once after his hand was cut off," said witness Ibrahim Yare. "Then nurses whisked him away."

Al-Shabab has been gaining ground as Somalia's Western-backed government crumbles.

The arid, impoverished Horn of Africa nation has not had a functioning government since 1991, when clan-based warlords overthrew a socialist dictator. Pirates operate off its lawless coastline and analysts fear the failed state is a harbor for international terrorists.