San Bernardino attack: Couple behind shooting were radicalised from at least 2013
The couple behind the San Bernardino attack were radicalised at least two years ago and had discussed jihad and martyrdom as early as 2013, FBI director James Comey has said.
That was well before one of them came to the US on a fiancee visa, Mr Comey added while providing the most specific details to date about the pair's path toward extremism.
Investigators are also looking at whether the husband accused in the California shootings was planning an attack in 2012 but abandoned those plans, according to sources.
One week into its investigation, the FBI now believes that Syed Rizwan Farook and his wife, Tashfeen Malik, embraced radical Islamic ideology even before they had begun their online relationship and that Malik held extremist views before she arrived in the US last year, Mr Comey told the Senate judiciary committee.
Though the FBI believes the pair were inspired in part by Islamic State (IS) ideology - Malik pledged allegiance to the group's leader in a Facebook post around the time of last week's massacre - agents are still looking for other motivations and sources of radicalisation, especially because the couple's interest in extremism predates the terror group's emergence as a household name.
"Isil inspiration may well have been part of this, but these two killers were staring to radicalise towards martyrdom and jihad as early as 2013," said Mr Comey, using an acronym for IS. "And so that's really before Isil became the global jihad leader that it is."
The latest disclosure also suggests that the US government's vetting process failed to detect Malik's radicalisation when she applied for the visa, though Mr Comey said he did not know enough to say whether weaknesses in the visa process enabled her to enter the US.
"After this hearing today, every American will be asking the question, how did this woman come in on a fiancee visa?" said senator Chuck Schumer, a New York Democrat and member of the committee.
Malik came to the United States in July 2014 from Pakistan after being approved for a K-1, or fiancee visa, and married Farook the following month. Homeland security secretary Jeh Johnson has said the Obama administration is now reviewing the programme. He did not say what changes were being considered.
Malik's father, reached in Jiddah, Saudi Arabia, condemned his daughter's actions and said he is "very, very sad", adding: "I am in such pain that I cannot even describe it."
Her father, Gulzar Ahmed Malik, has been a resident in the kingdom since the early 1980s, the Saudi interior ministry said.
His daughter was from Pakistan but travelled to Saudi Arabia. A former classmate, Afsheen Butt, said Malik showed drastic changes after a trip to Saudi Arabia in late 2008 or early 2009.
Last week's shooting attack at a holiday party killed 14 people and left 21 injured. Former neighbour Enrique Marquez bought the two rifles used in the attack, officials say.
One law enforcement official said Mr Marquez has told investigators that he and Farook planned an attack in the United States in 2012 but abandoned the idea. Mr Marquez is a relative of Farook's through marriage. The official added it is unclear what spooked them into cancelling the apparent plot.
Mr Comey described the couple as an example of homegrown violent extremists who appear to have radicalised "in place", drawing a distinction between the San Bernardino attack and the one last month in Paris that officials suspect involved planning and training in Syria. He said the FBI did not yet know if the marriage was arranged by a foreign terrorist organisation.
The FBI has revealed little else of what it has learned about Farook and Malik and their planning, except for details about the weaponry they had, materials they had to make more pipe bombs and that both had been taking target practice.
A US official said on Tuesday that authorities are looking into a deposit made to Farook's bank account before the attack. The official would not elaborate further on the nature of the deposit or why it had caught the attention of investigators. A second official confirmed that the deposit was for 28,500 US dollars.