Islamists in southern Somalia have stoned a man to death for adultery but spared his pregnant girlfriend until she gives birth.

Abas Hussein Abdirahman, 33, was killed in front of a crowd of some 300 people in the port town of Merka.

An official from the al-Shabab group said the woman would be killed after she has had her baby.

Islamist groups run much of southern Somalia, while the UN-backed government only control parts of the capital.

Al-Shabab official Sheik Suldan Aala Mohamed said Mr Abdirahman had confessed to adultery before an Islamic court.

Last month, two men were stoned to death in the same town after being accused of spying.

A 13-year-old girl was stoned to death for adultery in the southern town of Kismayo last year.

Human rights groups said she had been raped.