Syrian air strikes pummel Aleppo. Time for an international no-fly zone?

Air strikes on Aleppo in northern Syria have killed hundreds of people in the past week. Regime forces are using "barrel bombs" on targets that reportedly include markets, hospitals, and schools. 

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Much of the northern Syria city of Aleppo, part of which rebels once optimistically called "Free Syria territory," has been reduced to rubble by a particularly fierce government bombing campaign. 

By most accounts, hundreds have been killed in the offensive, which has been going on for more than a week now. Civilian targets such as schools, hospitals, and markets have reportedly been targeted.

The Syrian Observatory for Human Rights, a Britain-based Syrian opposition group, said at least 65 were killed when "explosive-laden barrel bombs" were dropped on a market area Sunday, making it the deadliest day of the offensive, according to the Associated Press.

The use of barrel bombs is a particularly lethal development. They contain "hundreds of pounds of explosives and shrapnel that include metal shards and iron nails," according to a New York Times report from Dec. 16, one of the early days of the operation. Human rights groups have described them as "a particularly insidious weapon that kills indiscriminately." CNN reports that the bombs "can level entire buildings with one hit."

Eliot Higgins, who is behind the prominent Syria blog Brown Moses, described the evolution of the barrel bomb to the Canadian Broadcasting Corporation:

Barrel bombs have been used by Assad’s forces for more than a year, but they‘ve become much more powerful and sophisticated over that time, according to Eliot Higgins, an influential British blogger who uses social media to glean information about weapons used in the conflict.

“They were pretty much simple pipe bombs, the early ones, and the problem they had is that they would fall through the sky and the fuse would burn out too soon and they would explode in midair — they weren’t terribly effective,” he said in a phone interview. “These new types are four to five times bigger than the original ones. They’re absolutely massive.”

Mr. Higgins said that the barrel bombs may have been improvised in order to allow regime forces to use cargo helicopters in battle, one of several ways they have changed tactics during Syria's civil war.

The rebels have long used improvised weapons, given their limited resources, but the regime's turn to "do-it-yourself" weapons is much more recent, CBC reports. Ole Solvang, a researcher with Human Rights Watch, said that the use of barrel bombs may be an effort to avoid depleting its stock of conventional weapons. 

“Over the last year or so the Syrian air force has been conducting attacks daily all over Syria,” Mr. Solvang said. “It’s difficult to say how many bombs they have. They must start getting concerned at some point they would be running out.”

Barrel bombs are inaccurate weapons, making them particularly dangerous to civilians. In the case of the Aleppo bombings, Ole said his organization has been struggling to determine whether the raids targeted opposition military targets, or whether Assad forces were indiscriminately bombing neighbourhoods controlled by opposition forces to terrorize residents.

"So far, I have to say it looks like there government is just dropping bombs all over the place,” he said.

The relentless air offensive has renewed calls for world powers to impose a no-fly zone on Syria, a proposal that first appeared in the early days of the anti-government uprising but never gained traction because of Russian opposition, The New York Times reports.

The main Syrian exile opposition group, the National Coalition of Syrian Revolutionary and Opposition Forces, on Sunday issued a statement saying, “A no-fly zone, backed by the Western powers, is the only means to prevent the Assad regime from slaughtering the Syrian people.” The group said that global powers had a responsibility to prevent the international deal to dismantle Syria’s chemical weapons — reached in the fall after the United States threatened to strike the government after accusing it of using chemical weapons — “from offering Assad a license to kill.”

“The attacks today targeted marketplaces, schools where displaced families had taken refuge, and apartment buildings,” the statement said. “The regime continues to use the pretext of countering ‘terrorists,’ while employing weapons of mass slaughter.”