The United States called reports of execution-style slayings by Syrian government forces "brutal" and a Christian archbishop fled Syria with several priests after their offices were ransacked, news services reported on Monday.
U.S. State Department spokeswoman Victoria Nuland said that of more than 300 people killed some 150 had been killed in a single location around the Syrian capital Damascus. She cited reports from human rights activists that some were killed point-blank "in the most brutal way at the hands of the regime."
Syrian opposition activists say as many as 600 people, including women and children, were killed by government forces in the Damascus suburb of Daraya.
Also on Monday, fighter planes fired two rockets at targets on the eastern edge of Damascus, opposition activists said, the same day a military helicopter was apparently shot down by rebels.
It was the first time a warplane has struck areas close to the capital, an activist source told Reuters.
Video taken by activists showed a fighter plane swooping in on a built-up area. An explosion is heard and a voice says: "It is firing rockets."
320 found killed in Syria; rebels blame Assad
Abu Qais, a Sunni Muslim in the Syrian capital, told The Associated Press that six members of his extended family have been killed by gunmen who belong to the minority Alawite sect of President Bashar Assad. The gunmen who grabbed one of his distant cousins called up his family while they were torturing him "so they could hear his screams," said Abu Qais, an anti-Assad activist who spoke on condition his full name not be used for fear of reprisals.
Sectarian slayings between Syria's Sunni majority and the Alawite minority have been a grim reality of Syria's 17-month-old conflict, and they have only accelerated as the country falls into outright civil war. Sunnis have largely backed the uprising against Assad's rule, while the Alawites — members of an offshoot of Shiism — have firmly stood behind the regime, where they fill the leadership ranks.
And as tit-for-tat killings have swelled, so has the segregation of the two communities as they flee each other. In Damascus and other cities, Sunnis and Alawites avoid venturing into each other's neighborhoods for fear of being snatched. Some Alawite districts in the capital are now ringed with checkpoints manned not only by security forces but also residents who have taken up arms to protect their homes.
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Those in mixed neighborhoods flee their homes to move into safer enclaves dominated by their community — whether in the same city or in another part of the country.
"Mutual threats in Damascus have succeeded in triggering migration," said Fateh Jamous, an Alawite activist from Latakia, the Mediterranean coastal city where many Alawites have fled. Latakia itself has so far represented a sort of tense neutral ground — its population is about half Sunni, half Alawite. "That created a sort of balance of terror. So far, it has been generally peaceful," he said by telephone from Latakia.
Christians, too, are being caught up in the sectarian strife. The Catholic news agency Fides reported that the Melchite Greek Catholic archbishop of Aleppo, Jean-Clement Jeanbart, and a number of priests fled to Lebanon after their offices in Aleppo were ransacked
The Melchite Greek Catholic Church is a community of Middle Eastern Christians who are in full communion with Rome.
Fides said "unidentified groups who want to feed a religious war and drag the Syrian population into sectarian conflicts" attacked the Christian area in the old quarter of Aleppo.
A Byzantine Christian museum and an office of the Maronite Christian faith were also damaged, the report said.
There are several Christian groups in Syria, many of which have been in the region since pre-Islamic times.
Christians make up around 10 percent of the population and many have remained loyal to Assad, fearing that the majority Sunni Muslims would trample on religious rights if they took power.
However, some senior members of the opposition are also Christians.
Reuters and The Associated Press contributed to this report.
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