California shooter pledged allegiance to ISIS

Tashfeen Malik, the female shooter in this week's murder of 14 people in Californa reportedly swore allegiance to ISIS leader Abu Bakr al-Baghdadi on Facebook.

American news networks are reporting Malik's post was made on an account using a different name but unnamed US officials did not explain how they knew Malik made the post. The post has since been removed.

Fourteen people were killed and 21 wounded in Wednesday's attack. The couple stormed a party attended by Farook's San Bernardino County co-workers in what appeared to be a planned attack before dying in a shootout with police.

Malik and her husband Syed Rizwan Farook, 28, died in a shootout with police after the killings at San Bernardino, east of Los Angeles.

But the New York Times reported that there was no evidence that IS had directed the couple in the attack.

"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.

After the 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.

They had destroyed computer hard drives and other electronic equipment before the rampage took place, a US government source said on Friday.

Investigators are 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, a US ally.