WASHINGTON — Two notorious Islamic State detainees from Britain were brought to the United States on Wednesday to face federal charges over accusations that they jailed and tortured Western hostages, some of whom were beheaded, Justice Department officials said.

The transfer is a milestone in the saga of the two men, El Shafee Elsheikh, 32, and Alexanda Kotey, 36, who are half of an ISIS cell of four Britons called “the Beatles” — a nickname bestowed by their victims because of their accents — and known for their extreme brutality.

The American government has linked the group to the kidnapping and abuse of more than two dozen hostages, some of whom were ultimately beheaded for propaganda videos, including the journalists James Foley and Steven Sotloff.

The British extremists repeatedly beat the hostages they kept imprisoned in Raqqa, Syria, formerly the Islamic State’s self-declared capital, according to prosecutors. They subjected their hostages to abuses including waterboarding, mock executions, painful stress positions, food deprivation, beatings with sticks lasting 20 minutes or longer, chokeholds causing blackouts and electric shocks. They also forced their hostages to fight each other and to witness murders, court papers said.

indicted on multiple charges, including hostage-taking resulting in death and conspiracy to commit murder outside the United States. If convicted, the men could spend the rest of their lives in prison. They made an initial appearance on Wednesday in federal court in Alexandria, Va.