It would be a "game changer" if a mass shooting by a couple that left 14 dead in California is confirmed as an act of terrorism, US government officials say.
- Female shooter Tashfeen Malik pledged allegiance to IS leader on social media, reports say
- FBI searches couple's home, says "digital media" damaged
- Couple's apartment opened up to media
- Two mobile phones found crushed in a waste bin near shooting
- Malik's family in Pakistan questioned
Tashfeen Malik's path to accused mass killer in California began in a small city on the Indus River in Pakistan's Punjab province.
It was from here, when she was a toddler, that she moved with her father Gulzar 25 years ago to Saudi Arabia, where he became more deeply religious, more conservative and more hardline, according to a family member.
A picture has slowly emerged of the role and possible motivations of 27-year-old Malik in this week's killing of 14 people in California, including her apparent pledge of allegiance to the leader of the Islamic State militant group, according to US officials.
Malik, with her husband Syed Rizwan Farook, 28, is accused of storming a holiday party on Wednesday in San Bernardino, California, and opening fire in America's worst mass shooting in three years.
The intensive search for clues, extending to Pakistan and Saudi Arabia, could help US investigators piece together what drove Malik and her husband to leave their infant daughter with his mother, don assault-style clothing and carry out the shooting.
Malik, who entered the United States on a fiancée visa, and Farook, the son of immigrant parents from Pakistan who had worked as a health inspector, were killed in a shootout with police just hours after the attack.
US investigators were evaluating evidence that Malik, a Pakistani native who had been living in Saudi Arabia when she married Farook, had pledged allegiance to Islamic State leader Abu Bakr al-Baghdadi, two US government sources said.
They said the finding, if confirmed, could be a "game changer" in the probe.
FBI Director James Comey said there were indications that the couple had been radicalised.
The couple were "potentially inspired" by foreign terror groups, he said.
There was no evidence that IS had directed the couple in the attack, The New York Times reported.
"At this point we believe they were more self-radicalised and inspired by the group than actually told to do the shooting," the newspaper quoted an official as saying.
Malik had reportedly made the pledge to al-Baghdadi in a posting on Facebook on Wednesday, the day of the attack, under an account that used a different name.
Though large information gaps remain, it appeared to be the strongest evidence so far that the attack may have been inspired by Islamic State. But US government sources said there was no sign that it had been directed by the militant group, which has seized swathes of Syria and Iraq and claimed the deadly November 13 attacks in Paris.
Father became conservative and hardline
Two Pakistani officials said Malik was from Karor Lal Esan, a city on the west coast of the Indus River in southern Punjab province. She moved to Saudi Arabia with her father, an engineer, 25 years ago, they said.
She returned home five or six years ago to study at Bahauddin Zakariya University in Multan to become a pharmacist, they said.
The area in Punjab where she spent her early years and later went to university is a "recruitment ground" and stronghold of Islamist groups with ties to al Qaeda, said Husain Haqqani, a former Pakistani ambassador to the United States. Among the militant groups with a presence there is Lashkar-e-Taiba, which has been blamed for the November 2008 killing spree in the Indian financial capital of Mumbai.
"Our brother changed a lot since he went to Saudi," Malik's uncle, Javed Rabbani, said of Malik's father.
"When relatives visited him, they would come back and tell us how conservative and hardline he had become."
A source close to the Saudi government said that during Malik's time in Saudi Arabia nothing came to authorities' attention there that suggested she was involved with radical Islamic groups. Malik was not on any Saudi law enforcement or intelligence watchlist, the source said.
Malik's father, Gulzar, had built a house in Multan, where he stays when he visits Pakistan, according to another uncle, Malik Anwaar.
He said Gulzar had a falling-out long ago with the rest of the family, citing a dispute over a house among other matters.
"We are completely estranged," Anwaar said.
Rabbani said he had been contacted by Pakistani intelligence as part of the investigation into the San Bernardino shooting.
Malik had two brothers and two sisters and was related to Ahmed Ali Aulak, a former provincial minister, the Pakistani officials said.
The exact circumstances of how Farook and Malik met remained unclear but they had apparently been married for two years. The Federal Bureau of Investigation said Malik was in the United States on a visa under a Pakistani passport.
While Farook had an active presence online, Malik's digital footprint is harder to trace. A Facebook profile established under an alias by Malik was removed by the company for violating its community standards, which prohibit praise or promotion of "acts of terror," a spokesman said on Friday.
But her name was attached to a gift registry for their baby hosted by the website TheBump.com. According to the registry, Malik's baby had been due on May 17.
Just hours before the couple opened fire on Farook's co-workers in a government building in San Bernardino, they had dropped off their daughter at his mother's house, telling her they had a doctor's appointment.
Police search couple's home, search for clues
After Wednesday's attack at the Inland Regional Center social services agency, bomb equipment, weapons and thousands of rounds of ammunition were found in the couple's home.
Authorities were trying to recover data from two mobile phones found crushed in a waste bin near the shooting scene, FBI spokesman David Bowdich said.
"Telephonic connections" had been established between the couple and other people of interest to the authorities.
As well as the possible allegiance to IS, investigators were also said to be following up a report that Farook had argued with a colleague at work who denounced the "inherent dangers of Islam".
Malik was born in Pakistan and had recently lived in Saudi Arabia.
Intelligence officials in Pakistan have contacted relatives there, a family member quoted by Reuters said.
Farook, who worked as an inspector for the city's environmental health department, was the son of Pakistani immigrants and born in the US state of Illinois.
Police said between 75 and 80 people were attending a party at the centre when the shooting began.
Officials said the attack indicated there had been "some degree of planning" and local police chief Jarrod Burguan said it appeared that the couple were prepared to carry out another attack.
"There was obviously a mission here. We know that. We do not know why. We don't know if this was the intended target or if there was something that triggered him to do this immediately," said David Bowdich, assistant director of the FBI's Los Angeles office.
In the shootout with police hours after the attack, Farook and Malik fired 76 rounds of ammunition. Officers fired 380 rounds back.
Two police officers were injured during the pursuit.
One of the first officers on the scene spoke of scenes of "unspeakable" carnage in the centre.
Lt Mike Madden said he and officers saw dead bodies and had to pass injured people as they tried to "engage the shooters" on Wednesday.
President Barack Obama - who is a fierce advocate of tighter gun controls in the US - said the FBI had taken over the investigation from local authorities.
The FBI, which has taken over the case from local authorities, cautioned that they needed time to investigate.
In another development on Friday, the couple's landlord opened their apartment to the media, prompting journalists and camera crews to go inside and survey the scene.
There has been strong criticism on social media, but the FBI had released the residence to the landlord before he let journalists in.
San Bernardino is the deadliest mass shooting in the US since 26 people were killed at a school in Newtown, Connecticut in 2012.
- Reuters/ BBC