Tashfeen Malik, the 27-year-old wife and accomplice of San Bernardino terrorist Syed Farook, 28, was in America on a K-1 (fiancée) visa and held a Pakistani passport.

Malik and Farook together carried out Wednesday’s deadly San Bernardino massacre, which left 14 dead.

Farook, who was a U.S. citizen, had reportedly travelled to Pakistan and returned to the U.S. in July 2014. Under U.S. immigration law, the K-1-visa-holding fiancée of an American citizen is permitted “to travel to the United States and marry his or her U.S. citizen sponsor within 90 days of arrival.”

After the couple married, Malik was given a green card, becoming a lawful, permanent resident.

It can take as little as three years for a K-1 visa recipient to become a naturalized U.S. citizen.

A chart presented by the Senate Subcommittee on Immigration last week reveals the U.S. issued 680,000 visas to migrants from Muslim nations over the last five years. The majority of those visas (83,000) were granted to immigrants from Pakistan.

According to CNN, “Farook traveled to Saudi Arabia for several weeks in 2013 on the Hajj, the annual pilgrimage to Mecca that Muslims are required to take at least once in their lifetime, which didn’t raise red flags, said two government officials. It was during this trip that he met Malik, a native of Pakistan who came to the United States on a ‘fiancée visa’ and later became a lawful permanent resident.”

The U.S. Department of State says that “the foreign-citizen will then apply for adjustment of status to a permanent resident (LPR) with the Department of Homeland Security (DHS), U.S. Citizenship and Immigration Services (USCIS). Because a fiancé(e) visa permits the holder to immigrate to the U.S. and marry a U.S. citizen shortly after arrival in the United States, the fiancé(e) must meet some of the requirements of an immigrant visa.”

During a Thursday press conference, law enforcement said that Farook was radicalized and had been in touch with people who were being investigated by the FBI for international terrorism. He had reportedly also been in touch with people with radical Islamic views both within the United States and abroad. Officials said Farook had communicated by phone and via social media with these terrorist suspects.

The terrorist couple was killed during a gun battle near the location of the massacre. They left behind a 6-month-old baby girl, in the care of relatives.

Breitbart’s Caroline May contributed to this report.

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