A small number of U.S. combat forces are in Uganda, part of a new effort to track down accused war criminal Joseph Kony and other leaders of the notoriously violent Lord's Resistance Army (LRA).

President Barack Obama sent a letter to top U.S. lawmakers Friday informing them that the first American troops landed in Uganda earlier this week. He says another combat team and other forces will deploy to the region over the next month.

The president's letter says the U.S. troops will help regional forces work toward “the removal of Joseph Kony from the battlefield.” The U.S. troops are to act as advisers, providing information, advice and assistance in Uganda, South Sudan, the Central African Republic and the Democratic Republic of Congo.

Mr. Obama said that American troops would only engage rebel LRA forces when acting to defend themselves.

The Lord's Resistance Army is accused of killing, kidnapping and mutilating tens of thousands of people across central Africa during a campaign that began in the late 1980s. Kony is wanted by the International Criminal Court for war crimes and crimes against humanity.

The U.S. has been supporting regional efforts to pursue Kony and the LRA, and to protect communities impacted by the LRA's campaign of terror.

Congress has also expressed support for increased efforts to eliminate the threat to civilians in the region.

In July, the United Nations Security Council issued a condemnation of the ongoing LRA attacks against people in central Africa. It demanded the LRA disarm and stop its atrocities, which have displaced 380,000 people in the region.

The Security Council praised the Central African Republic, the Democratic Republic of Congo, South Sudan and Uganda for banding together against the LRA.