One of the shooters in the San Bernardino massacre, Tashfeen Malik, sent at least two private messages on Facebook to a small group of Pakistani friends in 2012 and 2014, pledging her support for Islamic jihad and saying she hoped to join the fight one day, the Los Angeles Times reported on Monday.
The messages were posted before Malik, 29, entered the United States on a K-1 fiancée visa in July 2014, the Times said, citing two top federal law enforcement officials.
The messages were recovered by FBI agents investigating whether she and her husband, Syed Rizwan Farook, had been in direct contact with foreign militant organizations and were directed to carry out the Dec. 2 attack in which 14 people were killed, the Times reported.
The Times said the Facebook messages indicate for the first time that U.S. law enforcement and intelligence officials missed warnings on social media that Malik was a potential threat before she applied for her U.S. visa.
One of the officials characterized the messages as "her private communications ... to a small group of her friends," according to the Times. The official added, "it went only to this small group in Pakistan." The official said they were written in Urdu, an official language of Pakistan.
The second official said Malik "expressed her desire" in one of the posts to become an Islamic militant in her own right, the Times said. Both officials spoke on condition of anonymity, the newspaper said.
U.S. officials have said their investigation has yet to turn up evidence that foreign militants directed Farook or Malik when they stormed a holiday gathering of Farook`s co-workers and opened fire with assault-style rifles.
The couple fatally shot 14 people and wounded more than 20 in a rampage the FBI said it was treating as an act of terrorism inspired by Islamist militants.
Farook, the U.S.-born son of Pakistani immigrants, and Malik, a Pakistani native he married last year in Saudi Arabia, were killed in a shootout with police hours after the assault in San Bernardino, 60 miles (100 km) east of Los Angeles.
The FBI has said the couple declared they were acting on behalf of Islamic State. But FBI Director James Comey has said there was no evidence the militant group was aware of them before the attack.