President Donald Trump announced Friday night that he is immediately ending temporary legal protections for Somali migrants in Minnesota, striking at a program designed to shield certain foreign nationals from deportation.

Minnesota is home to the nation’s largest Somali community, many of whom fled decades of civil war and resettled in the state under its supportive social programs.

Officials say the number of migrants affected by the move is small. A report prepared for Congress in August estimated that just 705 Somalis nationwide hold Temporary Protected Status.

The program, created by Congress in 1990, allows migrants to remain in the United States when their home countries are unsafe due to natural disasters, armed conflict, or other crises. The designation is granted by the secretary of Homeland Security and is renewed in 18-month periods.

Trump announced the decision on social media, claiming Minnesota was “a center of fraudulent money laundering operations.”