American military forces bombed at least two targets in northern Iraq on Thursday night to rout Islamist insurgents who have trapped tens of thousands of religious minorities in Kurdish areas, Kurdish officials said.

Word of the bombings, reported on Kurdish television from the city of Erbil, came as President Obama was preparing to make a statement in Washington.

Kurdish officials said the bombings targeted fighters from the Islamic State in Iraq and Syria who had seized two towns, Gwer and Mahmour. Residents who had fled those areas by car were heard honking their horns in approval. But Rear Adm. John Kirby, the Pentagon press secretary, said on Twitter that the reports of the bombings were false.

Obama administration officials had said earlier in the day that Mr. Obama was considering airstrikes or airdrops of food and medicine to address a humanitarian crisis among as many as 40,000 members of religious minorities in Iraq, who have been dying of heat and thirst on a mountaintop where they took shelter after death threats from ISIS.