At least 200 members of the Allied Democratic Forces (ADF) rebels affiliated to the Islamic State group were killed in air strikes led by Uganda in September in the Democratic Republic of Congo (DRC), Uganda's president said Wednesday, AFP reports.

Originally Ugandan rebels with a Muslim majority, the ADF have been active since the mid-1990s in the Eastern DR Congo, where they have killed thousands of civilians.

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In 2019, they pledged allegiance to the Islamic State group, which now claims some of their actions and presents them as its "Central African Province" affiliate.

"We have been carrying out air attacks on the terrorists in Congo," President Museveni said on X, formerly Twitter, before claiming that around "200 of them were killed" in strikes carried out on September 16.

More strikes have been carried out since then, Museveni added without giving further details.

Contacted by AFP, Ugandan army spokesman Felix Kulayigye confirmed that the president was referring to the ADF rebels.

The rebels are accused of having massacred thousands of civilians in DR Congo in recent years and of carrying out jihadist attacks on Ugandan soil.

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Uganda and the DRC launched a joint offensive in 2021 to drive the ADF out of their Congolese strongholds but have so far failed to put an end to the group's attacks.

In March, the United States announced that it was offering a reward of up to $5 million for any information that would lead to the group's leader, a Ugandan in his forties named Musa Baluku.

In October, two tourists, a British man and a South African woman on their honeymoon, as well as their guide, were killed while on safari in Queen Elizabeth National Park in the west of the country, an attack claimed by the Islamic State group.

DR Congo: at least 20 dead in suspected ADF attack

Uganda arrested the leader of the ADF rebel group, accused of carrying out the murders in early November.

In June, 42 people, including 37 pupils, were killed in an attack on a secondary school in western Uganda also attributed to the ADF.

That was not the first attack on a school in Uganda blamed on the rebel group.

In 1998, 80 students were burnt alive in their dormitories during an ADF attack on the Kichwamba Technical Institute near the DR Congo border.

More than 100 students were abducted.