Former INLA prisoner Malachy McAllister is expected to be deported to Ireland from the US today.
Mr McAllister is understood to have turned himself in to US immigration authorities in New Jersey yesterday.
The former republican was jailed for seven years for two INLA attacks on RUC officers during the 1981 hunger strikes. He was released in 1985 and has lived in New Jersey for more than 20 years.
A US immigration appeals board ordered his deportation in 2003.
He has spent years fighting to remain in the US with several Irish-American groups and US politicians from both sides of the political divide lobbying on his behalf.
New Jersey Democratic Senator Bob Menendez criticised the US Department of Homeland Security for formally detaining Mr McAllister ahead of his deportation.
In a statement, Senator Menendez described Mr McAllister as a New Jersey resident and respected Irish community leader who escaped an assassination attempt in his native country and has lived peacefully in the US for decades.
"Today is a sad day for the McAllister family and New Jersey's Irish community. Deporting a community leader who poses no national security or public safety threat is not only a clear injustice, but also contrary to our nation’s values," Senator Menendez said.
Mr McAllister had been granted multiple stays of removal by the US Department of Homeland Security since 2007.