At least 35 Syrian soldiers and pro-regime militiamen were killed yesterday in a multi-front attack by the Islamic State group on the eastern city of Deir Ezzor, a monitor said.
The fighting came as regime forces battled IS in the northern province of Aleppo, repelling a militant assault and killing at least 16 fighters from the group.
The Syrian Observatory for Human Rights said IS had advanced into the northern tip of Deir Ezzor city, in eastern Syria, and captured the suburb of Al-Baghaliyeh.
The advance puts IS in control of around 60% of the city, with the regime holding the rest, according to the Britain-based monitor.
Syrian state news agency Sana said regime troops had repelled an IS attack on the area around Al-Baghaliyeh and inflicted “heavy losses” on the group.
Deir Ezzor is the capital of Deir Ezzor province, an oil-rich region that borders Iraq and is mostly held by IS.
The regime has clung onto portions of the provincial capital and the adjacent military airport despite repeated IS attacks.
Observatory chief Rami Abdel Rahman said heavy fighting was continuing yesterday afternoon after the IS assault, which began with a suicide car bomb blast carried out by a member of the militant group.
Eight of the regime forces killed were shot dead by IS militants, the Observatory added.
The monitor said Russian warplanes were carrying out heavy air strikes in support of regime forces as they sought to repel the militants.
Government-held areas in the city had been under siege by Islamic State fighters for more than a year and more than 200,000 people there are living in dire conditions lacking food and medicine.
A Syrian source said that the group has been trying to attack the city almost on daily basis and yesterday it “carried out several assaults. There are a number of civilians martyred.”
Islamic State supporters on social media said the group had also captured an army weapons depot.
Elsewhere, regime troops were locked in fierce clashes with IS in Aleppo province, with at least 16 militants killed after a failed attack on a government position near the town of Al-Bab, the Observatory said.
State television also reported that regime forces had repelled an assault.
The Observatory said heavy fighting was ongoing throughout yesterday in the area, with Russian war planes carrying out strikes in the region between the regime-held Kweyris airbase and Al-Bab.
The regime has advanced towards the town, an IS bastion, in recent days, and is now within 10km of it, according to the Observatory.
That is the closest regime forces have come to Al-Bab since 2012.
The Britain-based monitor also said regime forces had taken a string of villages nearby.
Roughly 30km south of the Turkish border, Al-Bab fell into rebel hands in July 2012, and IS militants captured it in late 2013.
The fighting in Al-Bab is just one of up to seven fronts on which regime forces are seeking to advance in Aleppo province, capitalising on a Russian air campaign that began on September 30
The various battles are intended in part to cut rebel supply lines into Aleppo city, the provincial capital and Syria’s second city.
The city itself is divided and regime forces are now hoping to effectively encircle the opposition-held east.

UN demands aid access to besieged towns
Condemning Syria’s “barbaric” sieges, the UN demanded immediate access to besieged towns to deliver food, medicine and other life-saving aid to civilians facing starvation. “There can be no reason or rational, no explanation or excuse, for preventing aid from reaching people,” UN aid official Kyung-Wha Kang on Friday told an emergency Security Council meeting on ending the blockades. France and Britain requested the urgent talks after reports emerged of dozens of people who have died from starvation in the town of Madaya, where aid deliveries finally arrived this week. A total of 35 people have died there since early December, according to medical charity Medecins Sans Frontieres (MSF), which warned a dozen more patients “could die very soon if they are not evacuated.” Madaya’s 40,000 residents have been living under siege by pro-government forces for months. “The barbarity of this tactic cannot be overstated,” Kang told the council. “You cannot let more people die under your watch.”