Gunmen killed three members of Yemen's security forces in an attack in the southern town of Zinjibar on Thursday, the defence ministry's news website said.
The gunmen killed Nasser Ahmed Al-Faqih, Hadi al-Ramadi and Alau al-Rabahi, 26sep.net quoted a local source as saying.
The search for the assailants is continuing, the source said.
Witnesses earlier said that three masked men attacked the security forces near the town's intelligence headquarters, killing two and wounding a third. The wounded man apparently died of his injuries.
An official at Al-Razi hospital in Jaar, just north of Zinjibar, said the bodies of three security forces members were brought in, all of whom had been shot in the head.
The assailants rode a motorcycle, with one of them carrying a Kalashnikov assault rifle in a black bag, a security official said.
South Yemen, where many residents complain of discrimination by the Sanaa government over the allocation of resources, is the site of frequent protests and periodic unrest.
The south was independent from 1967 until 1990 when it united with the north. It seceded in 1994, sparking a short-lived conflict which ended with the south bring overrun by northern troops.
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