BEIRUT, Lebanon — Islamic State fighters are preventing fuel shipments from reaching rebel-held parts of northern Syria, causing severe shortages that are paralyzing ambulances, stopping medical centers from providing care and shutting down bakeries, according to antigovernment activists and aid workers.
Adding to the misery, international aid groups said, the forces of Syria’s president, Bashar al-Assad, are targeting medical centers in opposition areas, killing some workers and forcing facilities to shut down.
The fuel shortages highlight how more than four years of war in Syria have ravaged the economy and allowed the warring parties to use the country’s scarce resources as a vise to squeeze their enemies.
Since the Islamic State, also known as ISIS or ISIL, seized oil-rich regions in Syria’s north and east, it has used their output to finance its efforts to build an Islamic emirate that straddles the Syria-Iraq border.
Traders from elsewhere in Syria, such as the rebel-held regions in the northwest, have long bought locally refined petrol products in ISIS-controlled areas and trucked them home, where residents came to rely on them to power their cars and fuel generators that powered clinics, bakeries and other essential facilities.
But this month, the jihadists began barring fuel trucks from leaving their areas, according to activists, aid workers and truckers.
“They are using fuel as a weapon,” said Dr. Khaled Almilaji, of the Canadian International Medical Relief Organization, which supports medical facilities in northern Syria.
The fuel embargo, Dr. Almilaji noted, comes as the Islamic State has been clashing with rebel groups as it seeks to expand in Aleppo Province. Dr. Almilaji said he presumed that the fuel cutoff was aimed at weakening the rebels to ease a jihadist advance.
But the cutoff has affected more than the rebels’ ability to fill up their trucks, he said. Clinics lacking electricity cannot treat the wounded, give dialysis or provide other essential services, the doctor said. Medical committees in Idlib and Hama Provinces have warned that they will have to shut down facilities soon if they do not receive fuel.
The shortages have also limited the movements of emergency medical workers in areas where the government frequently drops barrel bombs that destroy buildings and often leave civilians buried in the rubble.
“The most important thing is the ambulances and the civil defense trucks,” Dr. Almilaji said. “They cannot move in Aleppo and Idlib now, so if any barrel bombs are dropped, they can’t go dig the people out.”
Civilians across rebel-held parts of the northwest have described a mounting crisis as fuel supplies have dwindled, causing bakeries to cut production and grounding traders who move merchandise.
“For the time being, everything has stopped,” said an activist who would give only his first name, Hassan, adding that the price of a liter of gasoline, when available, had gone up fivefold.
A driver from the town of Jarjanaz said by phone that ISIS fighters had stopped him at a checkpoint as he was leaving their area and forced him to abandon his tanker truck.
“They said it was not allowed,” the driver said, speaking on the condition of anonymity because he worked in ISIS areas and feared retribution. “You can’t discuss with them. If they say it is not allowed, you have to obey.”
International aid groups sounded the alarm on Thursday about Syrian government attacks on medical facilities in opposition-controlled areas across the country.
Doctors Without Borders said that a hospital in Dara’a Province in the south had been destroyed after being struck by four barrel bombs this week.
The hospital was the only one in the province providing dialysis and neonatal care and has been closed indefinitely because of damage caused by the bombing, the group said in a statement.
Also on Thursday, Physicians for Human Rights said that May had been the worst month for attacks on health care facilities since the start of the Syrian conflict in March 2011, with 14 centers attacked and 10 medical workers killed.
The Syrian government was responsible for all of the attacks and for seven of the 10 deaths, the group said in a statement.
On Thursday, the United States and about 70 other countries sent a letter to the head of the United Nations Security Council to express their “outrage” at the Syrian government’s continued use of barrel bombs.
The letter is not expected to have any real effect, but the Council is scheduled to take up the issue of barrel bombs at a session next week.