WASHINGTON - The Pentagon says it sees signs that the Islamic State group is preparing for the loss of its de facto capital in Raqqa, Syria.

Navy Capt. Jeff Davis is a Pentagon spokesman. Davis says the extremist group's administrative structure in Raqqa is beginning to crack. He says IS "bureaucrats," those he describes as administrators and senior leaders, are fleeing east along the north bank of the Euphrates River in the direction of Deir el-Zour. He calls it an "exodus" and an organized withdrawal.

Syrian Arab and Kurdish fighters allied with the U.S. have been closing in gradually on Raqqa, blocking IS avenues of escape and reinforcement from the north and west.

The Trump administration is considering ways of accelerating its military campaign against the Islamic State in Syria and Iraq.