(Bloomberg) -- United Nations experts warned of growing communication between the Islamic State in Iraq and the Levant region and an Islamist rebel group in eastern Democratic Republic of Congo known as the Allied Defence Forces, or ADF.

Despite joint military operations against the group by the Congolese and Ugandan armies since November, the ADF has expanded its area of operations in gold and oil-rich Ituri province over the past year, the UN’s group of experts on Congo said in their annual report published Friday.

Communication between the Islamic State and the ADF “strengthened” during this time, though the experts could not document “direct support to and command and control over ADF.” The report warned that recruiters for the rebels were active throughout central Africa, “in particular along the Kenyan and Tanzanian coastlines and in Burundi.”

The ADF, which originated in Uganda more than two decades ago, has been linked to the death of more than 1,300 people since 2021, according to the UN, along with multiple bombings and attempted bombings in Congo, Uganda and Rwanda. The group has also stepped up its use of suicide attacks, sophisticated explosive devices and violent propaganda videos, the report said.

Read: Ugandan Police Blame Bombings on Islamic State-Linked Group

The insecurity has disrupted rehabilitation work on important trade routes connecting Uganda and northeastern Congo, which prompted the increased military cooperation between the two countries last year, according to the report.

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