Feb 10 - US federal immigration agents arrested hundreds of undocumented immigrants in at least four states this week in what officials on Friday called routine enforcement actions.Reports of immigration sweeps this week sparked concern among immigration advocates and families, coming on the heels of President Donald Trump's executive order barring refugees and immigrants from seven majority-Muslim nations. That order is currently on hold."The fear coursing through immigrant homes and the native-born Americans who love immigrants as friends and family is palpable," Ali Noorani, executive director of the National Immigration Forum, said in a statement. "Reports of raids in immigrant communities are a grave concern."The enforcement actions took place in Atlanta, New York, Chicago, Los Angeles and surrounding areas, said David Marin, director of enforcement and removal for the Los Angeles field office of US Immigration and Customs Enforcement.