As both secular and Islamic actors continue to stake their claims and fight for territory over war-torn Libya, Islamic State fighters have admitted to losing control of Derna, which was once identified as one of its stronghold cities, according to an AFP report.

A top ISIS leader said in a video posted on Twitter that he would avenge his fellow jihadis who died fighting for control of Derna, according to the report. In the 10-minute video, posted by the “media office of the [ISIS] province of Barqa,” Libya’s ISIS affiliate confirmed they had lost control of Derna.

Derna, which sits near the Egyptian border, has seen an influx of ISIS fighters since November 2014, the report states.

Michael Nayebi-Oskoui, a senior Middle East analyst at intelligence firm Stratfor, told AFP regarding the ISIS loss in Derna:

ISIS being kicked out of Derna does not dramatically alter the capabilities or effectiveness of the IS in Libya, as the group has faced and will continue to face stiff opposition from local competitors. ISIS remains constrained in its ability to retaliate for any potential loss in Derna… That said, attacks (including suicide attacks) against security checkpoints in and around Sirte, Benghazi and Tripoli are all possible.

ISIS’s most fierce competitor in the area is the Al Qaeda-affiliated Shura Council of Mujahideen in Derna, which operates as part of a Libyan Islamist coalition that seeks to install Sharia law in the area.

Although The Shura Council is fighting ISIS, it also opposes the secular armies of Libyan General Khalifa Haftar, who commands forces loyal to the country’s internationally recognized government.

Fighting between ISIS and the Shura Council dramatically escalated in June 2015, when ISIS gunmen assassinated senior Shura Council leader Nasser Akr. The Al Qaeda-linked group responded by declaring war against the Islamic terror group.

Members of the Shura Council, such as Ansar al-Sharia, are suspected of carrying out the 2011 attack on the American compound in Benghazi, Libya, which resulted in the deaths of U.S. Ambassador Christopher Stevens and three other Americans.