Syrians remove the bodies of those killed after a government airstrike hit the Hama Suburb of Halfaya, Syria.

BEIRUT - A government airstrike on a bakery in a rebel-held town in central Syria killed more than 60 people on Sunday, activists said, casting a pall over a visit by the international envoy charged with negotiating an end to the country's civil war.

The strike on the town of Halfaya left scattered bodies and debris up and down a street, and more than a dozen dead and wounded were trapped in tangled heap of dirt and rubble.

The attack appeared to be the government response to a newly announced rebel offensive seeking to drive the Syrian army from a constellation of towns and village north of the central city of Hama. Halfaya was the first of the area's towns to be "liberated" by rebel fighters, and activists saw Sunday's attack as payback.

"Halfaya was the first and biggest victory in the Hama countryside," said Hama activist Mousab Alhamadee via Skype. "That's why the regime is punishing them in this way."

The total death toll remained unclear, but the Britain-based Syrian Observatory for Human Rights said more than 60 people were killed. That number is expected to rise, it said, because some 50 of those wounded in the strike are in critical condition.

Amateur videos posted online Sunday showed residents and armed rebels rushing to the scene. One stopped to cover a mound of human flesh lying in the street with his coat.

More than a dozen dead or seriously wounded people lay in the street near a simple, concrete building, some in puddles of blood. Near its front wall, bodies jutted from a pile of dirt and rubble on the sidewalk.

Rebels screamed in distress while trying to extract the bodies, while others carried away the wounded.

It was unclear from the videos if the building was indeed a bakery. Nearly all the dead and wounded appeared to be men, some wore camouflage, raising the possibility that the jet had targeted a rebel gathering.

For the past week, rebels have been launching attacks in the area, most notably in the nearby village of Morek, where they hope to seize control of the country's main north-south highway, preventing the regime from getting supplies to its forces further north in the provinces of Idlib and Aleppo.

On Saturday, one rebel group threatened to storm two predominantly Christian towns nearby if their residents did not "evict" government troops they said were using them as a base to attack nearby areas.

The activist accounts could not be independently verified due to restrictions on reporting in Syria. The Syrian government does not respond to requests for comment on its military activities.

The attack coincided with the start of a two-day visit by Lakhdar Barhimi, who represents the U.N. And the Arab League, to meet with top Syrian officials.

Brahimi has made little apparent progress toward ending Syria's crisis since assuming his post in September, mostly because the sides appear more interested in fighting it out than in sitting down for talks.

Brahimi did not speak publicly upon arriving in Damascus for a two-day mission, and it was unclear whether he would present new ideas to end the war. His trip appeared troubled from the start.

Instead of flying directly to Syria as he had on previous visits, Brahimi landed in Beirut and traveled to the Syrian capital by land because of fighting near the Damascus airport, Lebanese officials said.

The Lebanese officials, who spoke on condition of anonymity because they were not authorized to brief reporters, said Brahimi was expected to meet Syria's foreign minister later Sunday and President Bashar Assad on Monday.

The trip is Brahimi's third since taking the job following the resignation of former U.N. Secretary General Kofi Annan after both sides disregarded a cease-fire he brokered in April.

While not advancing a comprehensive peace plan, Brahimi has called on the sides to negotiate a solution.

The security situation has gotten notably worse for the regime since his last visit, with rebels storming a number of military bases and seizing valuable munitions. Russia, Assad's most powerful international backer, also appears to have changed his assessment of Assad's strength, as top officials say they do not seek to preserve his regime, while still calling for a negotiated solution.

Still, neither side appears willing to talk.

In a lengthy Sunday news conference, Syrian Information Minister Omran al-Zoubi repeated the Syrian government's line that it is fighting terrorist groups backed by foreign powers who seek to destroy Syria.

Al-Zoubi said the government was willing to engage in dialogue but said the other side wasn't.

"We speak of dialogue with those who believe in national dialogue," he said. "But those who rejected dialogue in their statements and called for arms and use of weapons, that's a different issue. They don't want dialogue."

Rebel groups refuse to talk to Assad, saying too many people have died for him to be considered part of the solution.

Violence raged elsewhere in the country on Sunday. Anti-regime activists reported government airstrikes on suburbs east of the capital and the northern province of Aleppo.

Airstrikes on the town of al-Safira, south of Aleppo, killed 13 people, including a mother and five daughters from one family, a local activist named Hussein said via Skype. He gave only his first name for fear of retribution.

The town lies next to a large military complex with factories and artillery and air defense bases. Hussein guessed the airstrike was payback for recent rebel attacks on the complex.

"The strikes don't hit the fighters at all," he said. "They want to take revenge on the civilians."

The Observatory said at least 10 rebels and an unknown number of government troops were killed in clashes in Afreen, near Aleppo, Syria's largest city, as rebels sought to storm an army base there.

Anti-regime activists say more than 40,000 people have been killed since Syria's crisis began in March 2011.