Topeka, KS - Kansas is withdrawing from plans to resettle Syrian refugees in the state after the federal government failed to provide security information and files on the refugees, Republican Governor Sam Brownback said on Monday.

Brownback said in a statement that he repeatedly asked the administration of President Barack Obama for documentation on the screening of refugees that would be relocated from Syria to Kansas.

“Because the federal government has failed to provide adequate assurances regarding refugees it is settling in Kansas, we have no option but to end our cooperation with and participation in the federal refugee resettlement program,” Brownback said.

Kansas has received a trickle of Syrian refugees. A family of three and two men have been resettled there in the past 15 months, a spokeswoman for Brownback said by email.

The White House did not immediately have a comment on Brownback’s letter and the State Department did not immediately respond to a request for comment.

Obama pledged last year that the United States would take in 10,000 people fleeing war-torn Syria, under pressure from European leaders who have been inundated with refugees.

But the promise came under fire from Republicans concerned that violent militants could come into the United States posing as refugees.

More than 30 governors attempted to block refugees from their states, but courts and attorneys general have said that it is up to the federal government to screen refugees and settle them.

Brownback did not say in his announcement how many Syrian refugees were slated to be settled in Kansas and his press office could not immediately provide the number.

U.S. officials told a congressional panel in February that the country has tightened vetting of immigrants and refugees after attacks in California and Paris, and put on hold hundreds of applications from Syrian refugees.

More than four million Syrians have fled their war-torn country, according to the United Nations, which calls it the biggest refugee population from a single conflict in a generation.

Almost 2 million Syrian refugees are in Turkey and hundreds of thousands live in camps in Jordan, while others have flooded Greece, according to the U.N.