TRIPOLI, May 18 (Xinhua) -- Humanitarian coordinator of the UN Support Mission in Libya on Thursday called on the eastern-based Libyan army to allow humanitarian aid to enter the besieged eastern city of Darna.

"Some 300 to 500 families have reportedly been displaced from Al Fatayih area (east of Darna city), to Darna city as a result of the renewed conflict," Maria Ribeiro said in a report issued later on Thursday.

"Humanitarian access to Darna is severely limited and humanitarian supplies are awaiting approval to enter. The most urgent needs are in the health sector. If closures remain, humanitarian needs will increase," the report said.

Since the escalation of the armed conflict between the army and extremists in Darna in mid-May, at least six civilians have been killed and 14 injured, the report revealed.

The army is launching a military operation to take over Darna from the militants who control the coastal city.

Since 2015, Darna has been besieged by the army, which demands the Shura Council of the Mujahideen in Darna, a coalition of Islamist militias seeking to implement Sharia law in the city, leave. The army accuses the armed group of being loyal to al-Qaida.