WASHINGTON (AP) — Four U.S. senators are urging President Donald Trump to use the Guantanamo Bay detention center to hold fighters from the Islamic State group captured in Syria.

The Republican lawmakers say Islamic State prisoners could escape or be released in Syria, and they would face “justice” at the detention center on the U.S. base in Cuba.

Sens. Tom Cotton of Arkansas, John Cornyn and Ted Cruz of Texas and Marco Rubio of Florida made the suggestion in a letter sent Tuesday to the president.

The issue has come up because Trump has ordered the withdrawal of U.S. forces from Syria and U.S. allies there hold hundreds of IS prisoners.

Trump when he took office reversed an order from President Barack Obama to close the Guantanamo detention center. There are 40 prisoners still held there.