The Trump administration has paid informants embedded within a caravan of Central American migrants who are leaking information about the group’s movements and other details to Homeland Security officials, according to a report published Tuesday afternoon.

An NBC report did not specify how many informants the department had inside the moving group, whether they were migrants or U.S. officials, and how much they are being compensated. U.S. officials on Monday estimated that up to 10,500 people were traveling to the U.S. in a handful of different cararvans.