Every immigrant leaving the U.S. through one of the 30 biggest airports would have to be fingerprinted by federal authorities under an immigration reform measure that won early committee approval in the Senate on Monday.

The plan approved by the Senate Judiciary Committee is a concession to Republicans and some Democrats who support establishing a nationwide biometric tracking system at all U.S. air, sea and land ports of entry, a key recommendation made by the bipartisan 9/11 Commission after the Sept. 11, 2001, attacks to track potential terrorists entering or leaving the country.

The committee rejected a similar GOP proposal last week that would have forced the Department of Homeland Security (DHS) to establish a biometric immigration tracking system at every U.S. air, sea and land port of entry. The committee's Democrats and the four members of the bipartisan "Gang of Eight" who wrote the immigration bill and sit on the panel said such a plan would be too expensive.