Debris lie near a building damaged by a jet's missile in Aleppo, Syria, on Oct. 23.
Syrian government forces killed at least 20 people on Tuesday when they shelled a bakery in a neighborhood under rebel control in the contested northern city of Aleppo, opposition activists said.
The dead included women and children, they said. Video footage, which could not be immediately verified, showed decapitated bodies amid scattered bread loaves.
Two shells hit the bakery, located in the eastern Hananu neighborhood, in the early afternoon, said Majd Nour, an opposition campaigner in Aleppo. Free Syrian Army fighters were guarding it at the time, he said.
Aleppo is Syria's biggest city and commercial hub. Rebels trying to overthrow President Bashar al-Assad launched an offensive to capture it last month and street fighting has taken place on a daily basis since then.
Shell lands in Turkey
Earlier in the day an anti-aircraft shell fired from Syria hit a health center across the border in Turkey's Hatay province but there were no immediate reports of injuries, CNN Turk television reported.
Turkey has bolstered its military presence along its 560-mile border with Syria and has been responding to gunfire and mortar shells hitting its territory from fighting between Syrian rebels and government forces.
The district governor's office said it had no immediate information on the incident.
Tension between the two neighbors, once close allies, is at its highest since Ankara turned against Assad last year over his violent crackdown on anti-government protests.
International mediator Lakhdar Brahimi, who ended a four-day visit to Damascus on Tuesday, has pushed for a ceasefire to mark the Islamic holiday of Eid al-Adha, which starts on Friday, hoping for a respite from daily death tolls of around 150.
For a fourth straight day, Turkey's border with Syria is the scene of intense fighting. NBC's Ayman Mohyeldin reports.
But he did not win a public commitment to a truce in his talks with Assad, and the rebels say there is little point to a ceasefire that cannot be monitored or enforced.
The Turkish military has fired on Syria 87 times, killing 12 Syrian soldiers and destroying several tanks in retaliation for Syrian shells and mortar bombs landing inside Turkey, the Turkish newspaper Milliyet reported on Saturday.
In Syria, fighting raged on Tuesday as rebels battled to seize an army base close to the main north-south highway. The rebels say its capture would be a big step toward creating a "safe zone" allowing them to focus on Assad's southern strongholds.
Battle for Wadi al-Deif
Assad is fighting an insurgency that grew out of protests 19 months ago and has escalated into a civil war in which 30,000 people have been killed. His overstretched army has lost swathes of territory and relies on air power to keep rebels at bay.
For two weeks Assad’s forces have been tied down, battling rebels in Wadi al-Deif, east of the town of Maarat al-Numan. If the town fell to rebels, who already control northern border crossings to Turkey, Assad would be dependent on a single land route - from the Mediterranean port of Latakia - to supply his forces fighting to win back Aleppo.
"The battle started 11 days ago. At first we sent small groups to liberate (the base) and we were surprised by the resistance the regime forces showed," said Lieutenant-Colonel Khaled Hmood, a former army officer who defected to fight Assad.
Fabio Bucciarelli / AFP - Getty Images
A look back at the violence that has overtaken the country
"The regime is fighting fiercely. It seems that it doesn't care if it loses thousands of troops in order to keep its control over the compound."
Hmood said he believed around 400 soldiers were defending Wadi al-Deif - a group of barracks barely 500 yards from the Damascus-Aleppo road and backed by air power that Assad has deployed against rebels and residents of a nearby town.
The base may also be an important fuel depot, holding at least five million liters of kerosene in five underground bunkers, according to Hmood.
Anti-Assad activists say 40 civilians were killed in air strikes on the town last Thursday in one of the most intense air offensives of the Syrian conflict.
But its efforts to send military reinforcements have been repulsed by the besieging rebels. The last attempt on Sunday ended when four tanks were destroyed and the remnants of an army column had to pull back. "We have noticed that the best strategy is to hit its supply line. We have been harming the regime a lot by hitting the reinforcements it is sending."
The rebels still face challenges to take the base. Although they have acquired increasingly deadly arms, including artillery and anti-aircraft weapons, they have regularly complained that they have only limited supplies to keep up the fight.
Reuters contributed to this report.
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