DAMASCUS, Syria -- They fall randomly, often during rush hour, smashing into schools, businesses, churches and homes in the Syrian capital and leaving a trail of death and terror in their wake.
As President Bashar Assad's forces press ahead with a crushing offensive, rebels are increasingly hitting back by sending volleys of mortar shells crashing into central Damascus, hoping eventually to loosen the leader's firm hold on the capital.
Dozens of shells have struck the historic city center and surrounding areas in the past two weeks, launched from rebel-held neighborhoods on the outskirts. Mortar shells, many homemade, are known to be imprecise so it's not possible to determine whether the rebels fire them randomly or at specific targets.
Much of the shelling in recent weeks has centered on Christian-majority areas in the Old City, where many residents now barricade themselves at home and schools are half empty. Businessmen say sales have plunged, because people no longer dare to go out.
"Shells have become part of our everyday life," said Jean Nahhas, an 18-year-old business administration student who lives in the predominantly Christian area of Qassaa, which has been particularly hard hit by the shelling.
Nahhas, whose uncle was killed in shelling a month ago, said he and other Syrians have established a routine, going home early and calling to check on family and friends after each explosion.
Assad retains strong support in the capital, particularly among minority sects including Christians, Alawites, Druse and Shiites, making them likely targets. Foreign embassies and schools also are frequently hit. Rebels are overwhelmingly from the country's Sunni majority sect, and Christians are convinced that Islamic extremists among the fighters are deliberately targeting their neighborhoods.
"They fire randomly to force Christians to leave," Damascus-based Greek Orthodox Patriarchal Assistant Bishop Luca al-Khoury said in a telephone interview.
On Thursday, a mortar shell landed inside the Russian Embassy in Damascus, killing one Syrian and wounding nine, including guards, the Russian Foreign Ministry said. The embassy building sustained minor damage.
More than 100 people have been killed in mortar attacks on Damascus since this summer, according to reports by the Syrian state news agency SANA and the British-based activist group, the Syrian Observatory for Human Rights. That has punctured the sense of normalcy that the government has tried hard to cultivate. For the first two years after the uprising against Assad began in March 2011, the ancient city with its historic markets, mosques and churches was largely insulated from the bloodshed and destruction that plagued other areas.
Syria's deputy foreign minister, Faisal Mekdad, pointed to the recent "dangerous escalation" in mortar strikes during a meeting Thursday with foreign ambassadors and criticized the failure of Western countries to condemn them.
The death toll and damage is relatively minor compared to other, opposition held urban centers, which have been battered — in some cases entire blocks have been leveled — by Syrian army warplanes, heavy artillery and street fighting.