US shooting: Tasfeen Malik 'made Facebook pledge' to IS

The woman involved in a deadly gun attack in California pledged allegiance to the leader of the Islamic State (IS) group on Facebook, US officials say.

Tashfeen Malik made the post under an account with a different name, the officials told US media.

Fourteen people were killed and 21 wounded in Wednesday's attack.

Malik, 27, and her husband Syed Rizwan Farook, 28, died in a shootout with police after the killings at San Bernardino, east of Los Angeles.

David Willis reports from San Bernardino.