Gunmen ambush and kill four soldiers in south Yemen

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ADEN, Yemen, July 28 (Reuters) - Gunmen killed four soldiers on Tuesday in an ambush in south Yemen, the scene of several deadly protests in recent months against the central government, a security source said.

The source said a fifth soldier was wounded in the attack in Abyan province east of Aden, which he blamed on "destructive elements" without giving more details.

Yemen, a mountainous Arabian Peninsula country of 23 million, has been battling a wave of al Qaeda attacks over the past two years and a Shi'ite rebellion in its north, as well as an increasingly restive south angry over marginalisation.

The violence has raised Western fears that the ancestral home of al Qaeda leader Osama bin Laden, where poverty has fed lawlessness in outlying regions with weak government control, is becoming a new haven for Islamist militants.

Earlier on Tuesday, an explosion damaged the offices of the ruling party, the General People's Congress, in Abyan's provincial capital of Zinjibar, an opposition website ( said. There was no report of injuries.

Residents said the blast also damaged the nearby offices of another party and a private house.

At least eight people were killed in clashes between security forces and armed men on Thursday at an opposition gathering in Abyan. The gathering was held to demand the release of detainees held during recent disturbances. (Reporting by Mohammed al-Mokhashef; writing by Andrew Hammond and Firouz Sedarat; editing by Robin Pomeroy)