A Liberian refugee living in Southwest Philadelphia agreed Thursday to voluntarily leave the United States after becoming the latest target of federal investigators seeking justice for atrocities committed during the bloody civil war that gripped the West African nation in the 1990s.

Isaac T. Kannah, 51, admitted last year that he had lied about the role he played in the multifactional conflict in sworn testimony he gave in 2011 on behalf of a former wartime ally who faced deportation proceedings.

Kannah's sentence, approved Thursday by a federal judge in Rochester, N.Y., makes him the third member of the Philadelphia region's sizable Liberian expatriate community to be swept up this year in a push by U.S. investigators to root out and deport those involved in the many documented human rights violations that occurred during the fighting.

Despite atrocities committed on all sides, no one has ever been held accountable in Liberia in the two decades since the end of the conflict that left more than 250,000 Liberians dead and millions more displaced. Many former military commanders are now living in the United States amid the flood of asylum-seekers who were welcomed into Philadelphia and other cities at the height of the crisis.

Kannah — a self-described military attaché to the Liberia Peace Council, one of the many fighting factions – first came to the attention of federal authorities in 2011, when he was called as a defense witness in immigration proceedings for the group's former leader, George Boley.

Government lawyers had accused Boley, then working as an administrator in the Rochester school system, of lying about the fighting force he oversaw, which committed extrajudicial killings of civilians and conscripted children to serve as soldiers.

Kannah, however, challenged that portrayal on the witness stand and insisted that the LPC was not engaged in fighting during the war.

"I don't have any question in my mind," he said, according to transcripts. "I'm sure of what I'm saying."

But in an indictment filed shortly after Boley was deported in 2012, prosecutors in Rochester accused Kannah of lying, pointing to a statement he had given immigration investigators just months before his testimony. In it, he had boasted of himself and Boley as the victors in a 1994 guerrilla-style military campaign against rival warlord Charles Taylor. Prosecutors also accused the two men of fighting alongside child soldiers during the attack.

Kannah pleaded guilty last year to a lesser felony count, alleging he failed to notify authorities that he knew Boley had lied during the 2011 proceeding.

Few details of Kannah's life since the war's end were available Thursday. Neither he nor his attorney Jeffrey L. Ciccone returned calls for comment.

Court papers say only that Kannah arrived in the U.S. seeking asylum in 1997, shortly after Taylor was elected Liberia's president. Public records reveal few additional details except that he was living in Reading during Boley's court proceeding and moved to Philadelphia shortly afterward.

U.S. Homeland Security Investigations agents arrested Kannah in January 2017, around the time they were preparing for trial in cases against two of his countrymen living in the region.

One of those men – Jucontee Thomas Woewiyu, 73, of Collingdale, Delaware County — was convicted this month of lying on a 2006 application for U.S. citizenship about the role he played as Taylor's top lieutenant and spokesperson. He faces sentencing in October.

The other – Mohammed "Jungle Jabbah" Jabateh, 51, of East Lansdowne — is serving a 30-year prison term after a jury found him guilty last year of similarly deceiving authorities about his past as a vicious warlord who had committed numerous rapes, murders, and acts of cannibalism during the fighting.

Justice Department officials have described the cases against all four men – Boley, Kannah, Woewiyu, and Jabateh – as part of a broader U.S. effort to protect the nation's political asylum system from abuse and to provide Liberia's war victims with justice they have been denied in their own country.

Since the war's end, persistent calls for a homegrown war-crimes tribunal have gone unanswered by Liberia's elected leaders – some of whom were directly involved in the fighting.

Boley, for instance, returned home and went on to win a seat last year in Liberia's House of Representatives after his 2012 deportation.