ORLANDO, Fla. -

A Muslim rights organization is asking Secretary of State John Kerry to intervene and allow three permanent residents of Florida to return to the United States from Russia.

The Florida chapter of the Council on American-Islamic Relations sent a letter to Kerry on Monday accusing the United States of unlawfully preventing three Russians -- Umar Taramov, Khusen Taramov and Khasan Taramov -- from boarding a flight in Moscow.

Khusen Taramov was one of the last people to see Chechen immigrant Ibragim Todashev alive before he was shot to death in May during an interview with the FBI and others in Central Florida.

Officials say Todashev turned violent while being questioned about his ties to one of the Boston Marathon bombing suspects. The state attorney is continuing to investigate the incident.