Separatists in said they have taken control of an important base in the country's , according to a report on Sunday.
Mohammad Al-Naqeeb, a spokesperson for the Southern Transitional Council (STC), said the site was located in Mudiyah district.
Al-Qaeda militants carried out attacks in Abyan's capital of Zinjibar from the base, Al-Naqeeb was cited as saying by Turkish news agency Anadolu.
Two STC fighters – one of them a senior commander – were killed in the effort to capture the site.
Al-Qaeda militants previously killed at least 22 fighters from the UAE-trained Security Belt Forces, which are linked to the STC, in Abyan.
The then began an anti-terror campaign in the province, where it shares control with Yemeni government forces.
Attacks on military bases in the province are common and Al-Qaeda militants are typically said to be responsible.