BENI, Democratic Republic of Congo — Suspected Islamist rebels killed at least 17 people in an attack on civilians working fields in east Democratic Republic of Congo on Tuesday, a local official and a hospital worker said on Wednesday.

The attack targeted residents of the town of Oicha in Congo's North Kivu province, a mineral-rich area that has been plagued with militia violence left over from a civil war that ended at the turn of the century.

The victims were tending crops around 20 km (12.43 miles) west of the town.

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Oicha Mayor Nicolas Kikuku blamed members of the Allied Democratic Forces (ADF), an Islamic State-linked group originally from neighboring Uganda that is now in east Congo and frequently attacks civilians.

By Wednesday evening, 17 bodies had been taken to the morgue of Oicha's general hospital on motorbikes, Kikuku said.

The head of the morgue, Kakule Sekera, said 19 bodies had been delivered so far, including two women. Some had their heads severed.

"The victims have been decapitated with machetes," Sekera said.

The vice-president of a local civil society group, Patrick Kakule Mukohe, said he had counted 17 bodies at the morgue so far but that he had heard of 31 victims in total.

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"We think the other bodies will come later," he said.