WASHINGTON — Immigration officials are moving to deport at least 150 Bosnians living in the United States who they believe took part in war crimes and “ethnic cleansing” during the bitter conflict that raged in the former Yugoslavia in the 1990s.

In all, officials have identified about 300 immigrants who they believe concealed their involvement in wartime atrocities when they came to the United States as part of a wave of Bosnian war refugees fleeing the violence there. With more records from Bosnia becoming available, the officials said the number of suspects could eventually top 600.

“The more we dig, the more documents we find,” said Michael MacQueen, an Immigration and Customs Enforcement historian who has led many investigations in the agency’s war crimes section. The accused immigrants, many of them former soldiers from Bosnia, include a soccer coach in Virginia, a metal worker in Ohio and four hotel casino workers in Las Vegas.

The effort to identify suspects included an appeal broadcast to Bosnians around the world in February, urging witnesses to come forward with any information about war crimes. Bosnians should be confident that “justice can be served in the United States despite the fact that many years have gone by and that the conduct occurred overseas, far away,” Kathleen O’Connor, a human rights prosecutor at the Justice Department, said in a message translated into Bosnian on the government-financed Voice of America network.