Attack took place during a Sunday service in the eastern city of Kasindi, the army said.

An army spokesman said the attack during the Sunday service in the city of Kasindi, on the border with Uganda, was likely carried out by the Allied Democratic Forces (ADF), a Ugandan armed group that has pledged allegiance to ISIL (ISIS).

“Despite the security measures put in place, the first indications show that it is the ADF which is behind this bomb attack,” Anthony Mualushay told Reuters news agency.

“I just came back from the scene, where I saw the bodies of children on the ground,” Alain Kitsa, a Kasindi resident, said, describing the atmosphere in the town as tense.

The ADF, which began as an uprising in Uganda but has been based in the DRC since the late 1990s, has not claimed responsibility for the bombing.

Kasindi is in a province where Congolese and Ugandan forces have launched a campaign against the ADF.

It pledged allegiance to ISIL in mid-2019 and is accused of killing hundreds of villagers in frequent raids over the past two years.

More than 120 armed groups roam mineral-rich eastern DRC, many are the legacy of regional wars that flared at the turn of the century.