DAMASCUS, Syria (AP) -- The sound of artillery reverberated Thursday through a predominantly Christian village north of Damascus as government troops and al-Qaida-linked rebels battled for control of the mountainside sanctuary.
The hit-and-run attacks on the ancient village of Maaloula, one of the few places in the world where residents still speak Aramaic, highlighted fears among Syria's religious minorities about the growing role of extremists among those fighting in the civil war to topple President Bashar Assad's regime.
The fighting came as President Barack Obama's administration pressed the U.S. Congress for its authorization of a military strike against the Assad regime, while the president arrived at a G-20 summit in Russia expected to be overshadowed by Syria.
The fighting in Maaloula, a scenic village of about 3,300 perched high in the mountains, began early Wednesday when militants from Jabhat al-Nusra stormed in after a suicide bomber struck an army checkpoint guarding the entrance.
The group -- listed as a terrorist organization by the U.S. State Department -- is one of the most effective fighting forces among Syrian rebels. The suicide attack triggered battles that terrorized residents in the village, famous for two of the oldest surviving monasteries in Syria -- Mar Sarkis and Mar Takla.
Online video showed rebels in the streets, some firing truck-mounted heavy machine guns in the direction of the surrounding mountains. The video appeared authentic and matched Associated Press reporting on the fighting.
Residents said Wednesday the rebels took over the mountaintop Safir hotel and were firing in the direction of the community below.
Rami Abdul-Rahman, director of the Britain-based Syrian Observatory for Human Rights, said that despite a heavy army presence in the village, the rebels staged hit-and-run attacks, at one point patrolling the streets on foot and in vehicles, and briefly surrounding a church and a mosque before leaving early Thursday.
Heavy fighting around the village, which is on a UNESCO list of tentative world heritage sites -- continued throughout the day, and heavy artillery echoed in the village.
"The stones are shaking," said a nun at the Mar Takla monastery. "We don't know if the rebels have left or not, nobody dares go out."
Frightened residents expected the militants to return to the Safir hotel, she said, adding: "It's their home now."
She spoke with the AP on condition of anonymity for fear of reprisals.
Al-Mayadeen TV, a Lebanese station who has an embed with the Syrian army, broadcast live images from the area Thursday evening that showed smoke rising from behind the hotel, suggesting the military was shelling it.
The nun said about 100 people from the village took refuge in the St. Takla convent that she helps run. The 27 orphans who live there had been taken to nearby caves overnight "so they were not scared," she said.
Maaloula, about 40 miles (60 kilometers) northeast of Damascus, had been firmly under the regime's grip, despite sitting in the middle of rebel-held territory east and north of the capital. The village was a major tourist attraction before the civil war. Some of its residents still speak a version of Aramaic, the language of biblical times believed to have been used by Jesus.
In 2008, Assad and his wife, Asma, visited the St. Takla convent, eating with Christian orphans there. In the same year, Assad took former U.S. President Jimmy Carter for a stroll in the area.
The attack highlights fears among Syrian Christians that the alternative to Assad's regime, made up mostly of Alawites -- followers of an offshoot of Shiite Islam -- would not tolerate minority religions.
The nun who spoke to AP said there were reports that the militants threatened villagers with death if they did not convert. The report could not be independently confirmed.
Such fears have allowed Assad to retain the support of large sections among Syria's minorities, which includes Christians, Alawites, Druze and ethnic Kurds, throughout the 2½ year civil war. Most of the rebels and their supporters are Sunni Muslims.
Elsewhere Thursday, a car bomb exploded outside a research center belonging to the Ministry of Industry in the area of Soumariya near Damascus, killing four people and wounding several others, a government official said. The official who spoke on condition of anonymity because he was not authorized to talk to reporters.
Three people were wounded when mortar shells hit two residential neighborhoods of Damascus, the state news agency SANA reported.
In the northern province of Aleppo, a Syrian surgeon working for an international aid group was killed. Doctors Without Borders said the 28-year-old surgeon, Muhammad Abyad, died in an attack. Abyad, whose body was found Tuesday, had been working in an Aleppo hospital run by the group.