Contaminated water and a lack of sanitation in flood-hit eastern Libya means people there are at serious risk of disease outbreaks, the UN has warned.

It says teams from nine UN agencies are giving humanitarian aid, including emergency medical kits that will support 15,000 people for three months.

Thousands of people were killed when two dams above Derna broke during a powerful storm a week ago.

So far 11,300 people are known to have died, according to the UN, and more than 10,000 remain missing.

"The UN in Libya continues to co-ordinate with Libyan authorities and international partners to ensure that the right aid, gets to the right people, at the right time," it said in a statement.