Damascus, June 26 (IANS): The Islamic State (IS) militants on Friday advanced into Syria's northern city of Hasaka amid ferocious battles with the Syrian government forces, according to activists.

The IS continued to advance against the government forces, storming the central prison of Hasaka, and releasing all inmates, Arab media cited the IS reports as saying.

The Syrian Observatory for Human Rights said 20 security forces were killed on Friday when the IS militants blew up a car bomb near a security headquarters in Hasaka.

The state news agency SANA said the IS militants blew up a booby-trapped vehicle near an intelligence headquarters in the city, spelling no further details.

A day earlier, the IS militants unleashed a massive offensive against Hasaka, capturing the Nashweh neighbourhood in the southern part of the city, following intense battles with the Syrian forces.

Activists said the IS militants kept the momentum of their attack on Friday.

Syria's Minister of Information Omran al-Zoubi said Friday that defending Hasaka in the face of the terrorist group was the duty of every person in Hasaka, calling on all men capable of holding weapons to take part in defending the city against the massive offensive of the IS militants.