Around $100 million worth of crude oil has gone up in flames as a result of a blaze burning at a tank storage facility in Libya, the government said.

Militants with a group calling itself Libya Dawn launched attacks last week on the port of Es Sider, leaving oil storage depots in flames and at least 19 soldiers dead.

The state-run National Oil Corp. confirmed as many as five of the 21 tanks storing oil at the site are in flames, which represents about $100 million worth of crude oil.

The storage depot is next to the Ras Lanuf terminal, which has suffered several outages as opposing Libyan forces struggle to fill a power vacuum left over when the regime of Moammar Gadhafi collapsed during civil war in 2011.

The U.N. Support Mission in Libya condemned the violence.

"UNSMIL appeals to all sides to work towards de-escalation, and calls on them to take the courageous steps to stop this cycle of violence which, if it continued, will lead the country to chaos and all-out war," it said in a Sunday statement.

NATO forces operating under a U.N. mandate backed forces fighting Gadhafi loyalists during the civil war. Libyan Interior Minister Omar al-Sinki said some form of international assistance was needed to at least help control the blaze at Es Sider

The terminal is operated through a joint venture between the NOC and several U.S. oil companies. Combined with Ras Lanuf, the terminals can handle 560,000 barrels of oil per day, about half of the country's total export capacity. Pre-conflict oil production was higher than 1 million barrels per day, though output has slumped recently to as low as 330,000 bpd because of clashes in and around key oil fields.

A NATO official said that, despite enduring security post-civil war security challenges, the alliance is not discussing any military action in Libya.