The wife of Orlando nightclub gunman Omar Mateen was arrested by the FBI on Monday in connection to the mass shooting, officials said.

(NBC News) - The wife of Orlando nightclub gunman Omar Mateen was arrested by the FBI on Monday in connection to the mass shooting, officials said.

Noor Salman was taken into custody in California, where her family lives, but the case is filed in Florida, where her husband massacred 49 people at the Pulse nightclub in June.

"I can confirm the arrest did occur," Attorney General Loretta Lynch said on MSNBC.

"This is a matter that we continue to take very seriously," she said, adding that it was always the Justice Department's goal to to determine if "there is any other accountability that needs to be had in this case."

Details of the charges against Salman were not immediately made public, but law-enforcement sources said they are related to obstruction of justice.