WEST PALM BEACH, Fla. (AP) — The U.S. State Department said Saturday that it has “credible reports” that Hamas could violate the ceasefire with an attack on Palestinian civilians in Gaza.

If the attack takes place, it “would constitute a direct and grave violation” of the agreement forged by President Donald Trump to end the two-year war between Israel and Hamas, the statement said.

No further details were disclosed about the potential attack.

”Should Hamas proceed with this attack, measures will be taken to protect the people of Gaza and preserve the integrity of the ceasefire,” the State Department said.

Trump previously warned on social media that “if Hamas continues to kill people in Gaza, which was not the Deal, we will have no choice but to go in and kill them.”

The U.S. president later clarified he won’t send U.S. troops into Gaza after launching the threat against Hamas.

“It’s not going to be us,” he told reporters. “We won’t have to. There are people very close, very nearby that will go in and they’ll do the trick very easily, but under our auspices.”

Trump’s hostile rhetoric represented a shift after initially expressing nonchalance about Hamas killings, saying they had taken out “a couple of gangs that were very bad.”