* Islamist ADF blamed for attacks around Congo's Beni
* Islamic State claims attack against Congolese forces
* Armed groups hampering Ebola response (Adds Islamic State claim of attack)
By Fiston Mahamba
GOMA, Congo, May 30 (Reuters) - Congolese forces killed 26 rebels from a group thought to be linked to Islamic State on Thursday in a shootout in the country's eastern Ebola zone, the army said.
The clash took place in a village near the city of Beni, an area where more than a dozen different militia groups and associated armed gangs operate, and the epicentre of Democratic Republic of Congo's worst ever Ebola epidemic.
The army's spokesman for east Congo, General Leon-Richard Kasonga, said the insurgents from the Allied Democratic Forces (ADF) attacked an army position in Ngite village and that soldiers returned fire and pursued them.
"Twenty six rebels were neutralised by the army, and their bodies recovered," he told journalists in Goma.
The ADF has never claimed allegiance to Islamic State, but witnesses said the Congolese group carried out an attack last month in nearby Bovata that IS claimed.
Islamic State said on Thursday its 'Central Africa Province' had inflicted "dozens of casualties" on Congolese forces, according to the SITE Intelligence Group, which monitors online jihadist activity.
Its fighters had attacked three army barracks near Mavivi, which lies next to Ngite, and "returned safely to their positions," it said.
There was no independent confirmation of the claims.
The ADF, originally a Ugandan Salafist-inspired extremist group, has been operating along the Congo/Uganda border for more than two decades. Rival armed factions remain active in pockets of east Congo long after the official end of a 1998-2003 war in which millions of people died, mostly from hunger and disease.
Insecurity around Beni is also undermining efforts to contain the Ebola epidemic, which has killed close to 1,300 people since August. Militiamen attacked a hospital in the nearby city of Butembo last month and killed a Cameroonian doctor working for the World Health Organization (WHO). (Additional reporting by Djaffar Al Katanty Writing by Tim Cocks; Editing by Toby Chopra and John Stonestreet)
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