The FBI arrested three people on Thursday, including the older brother of San Bernardino shooter Syed Farook, on charges of marriage fraud and lying to investigators, authorities said.
Syed Raheel Farook, 31, was arrested in the early morning at his home in the California town of Corona, along with his wife Tatiana Farook, also 31.
Mariya Chernykh, Tatiana’s 26-year-old sister who lives in the nearby town of Ontario, was also arrested.
The five-count indictment against the trio centres on Chernykh’s alleged sham marriage to Enrique Marquez, who is awaiting trial on charges of aiding the December 2 attack carried out by Syed Farook and his wife Tashfeen Malik.
The pair were later killed in a dramatic shootout with police.
“This is the latest step in the comprehensive investigation into the horrific attacks in San Bernardino last year that took the lives of 14 innocent Americans and deeply affected so many more,” US attorney Eileen Decker said in a statement.
“As I have said previously, we owe the victims, and the entire community of San Bernardino, a thorough investigation that uncovers all criminal activity surrounding these events.”
The trio appeared in federal court after their arrest on Thursday and entered not guilty pleas, a Justice Department official said.
They were all given bail but were ordered to turn in their passports and banned from travelling outside Southern California pending their trial which was set for June 21, the official told AFP.