BAGHDAD -- Islamic State militants searched through the Syrian town of Palmyra for government troops and fighters, using lists of names and informers to track them down and shooting some in the head on the spot, activists said Friday, estimating at least 150 had been killed in the past two days.
The purge was part of a clampdown by the extremist group to solidify its grip on the town since overrunning it late Wednesday. The militants also imposed a curfew from 5 p.m. until sunrise and banned people from leaving town until this morning to ensure none of the government figures they seek manages to escape, activists and officials said.
The door-to-door hunt for opponents was similar to a purge the militants carried out in the Iraqi city of Ramadi after capturing it last week.
"The search is going from house to house, shop to shop, and people on the streets have to show identity cards," said Osama al-Khatib, an activist from Palmyra who is currently in Turkey.
Al-Khatib last contacted his friends and relatives in Palmyra on Friday morning before the government cut off all land and cellular telephones as well as Internet service in the town.
Islamic State fighters also detained dozens of suspects after seizing Palmyra, which is home to one of the Middle East's most famous archaeological sites, activists and officials said.
Homs-based activist Bebars al-Talawy said as many as 280 soldiers and pro-government militiamen had been killed in Palmyra since it was captured Wednesday. He said militants abducted soldiers and pro-government gunmen from homes, shops and other places where they had sought to hide. He added that many were shot dead in the streets.
Al-Khatib said some 150 bodies lay in the streets of Palmyra, including 25 members of the pro-government militia known as the Popular Committees who were Palmyra residents.
Maamoun Abdulkarim, the head of the Antiquities and Museum Department in the Syrian capital Damascus, said "there are arrests and liquidations in Palmyra." He added that fighters are "moving in residential areas, terrifying people and taking revenge."
Abdulkarim said no gunmen were seen in the area of Palmyra's 2,000-year-old ruins, which once attracted thousands of tourists.
The Britain-based Syrian Observatory for Human Rights said Islamic State fighters had killed 17 men in Palmyra and that it had unconfirmed reports of the killing of dozens more. The Local Coordination Committees, another activist group, said the militants had killed dozens of people since Wednesday.
Gov. Talal Barazi of the central province of Homs, which includes Palmyra, said the Islamic State had abducted men and "might have committed massacres." He added that about 1,400 families left the town of 65,000 before the militants started preventing people from leaving Thursday.
In neighboring Iraq, Islamic State militants seized another town in the western province of Anbar less than a week after capturing the provincial capital, a tribal leader said Friday.
Sheikh Rafie al-Fahdawi said the small Iraqi town of Husseiba fell to the militants Thursday night when police and tribal fighters withdrew after running out of ammunition.
"We have not received any assistance from the government. Our men fought to the last bullet and several of them were killed," he said.
Husseiba is about 4 miles east of Ramadi, where the militants routed Iraqi forces last weekend. Al-Fahdawi said that with the fall of Husseiba, the militants were closer to the strategic Habbaniyah military base, which is still held by government forces but "is now in great danger."
Also Friday, U.S. defense officials said Iran had entered the fight to retake a major Iraqi oil refinery from Islamic State militants, contributing small numbers of troops -- including some operating artillery and other heavy weapons -- in support of advancing Iraqi ground forces.
Two U.S. defense officials said Iranian forces have taken a significant offensive role in the Beiji operation in recent days, in conjunction with Iraqi Shiite militia. The officials were not authorized to discuss the matter publicly and spoke on condition of anonymity.
One of the officials said Iranians are operating artillery, 122mm rocket systems and surveillance and reconnaissance drones to help the Iraqi counteroffensive.
The Iranian role was not mentioned in a new U.S. military statement asserting that Iraqi security forces, with U.S. help, had managed to establish a land route into the Beiji refinery compound. The statement Friday by the U.S. military headquarters in Kuwait said Iraqis had begun reinforcing and resupplying forces isolated inside the refinery compound.
Iran's role in Iraq is a major complicating factor for President Barack Obama's administration as the U.S. searches for the most effective approach to countering the Islamic State. U.S. officials have said they do not oppose contributions from Iran-supported Iraqi Shiite militias as long as they operate under the command and control of the Iraqi government.
Information for this article was contributed by Robert Burns of The Associated Press.
A Section on 05/23/2015