A Kenyan police officer says 15 bodies have been taken to the morgue after an attack on a luxury hotel complex in Nairobi claimed by the al-Shabaab extremist group.

The officer spoke on condition of anonymity because he was not authorised to speak to reporters.

The al-Qaeda-linked al-Shabaab, based in neighbouring Somalia, has asserted that 47 people were killed but it gave no details in a post by its Shahada news agency.

Families have said some people are still hiding inside the complex.