The Syrian regime accused rebels yesterday of carrying out a “brutal massacre” of 25 of its supporters, as neighbouring Turkey held emergency talks after one of its warplanes went down in the Mediterranean..

Monitors said regime forces fired on demonstrators in Syria’s second-largest city Aleppo, killing at least eight people, with another killed in the province of the same name.

In neighbouring Turkey, the plane incident triggered an emergency summit of military, intelligence and government officials.

NTV private news channel quoted unnamed military sources as saying the plane crashed in Syrian territorial waters.

Turkish Prime Minister Recep Tayyip Erdogan, whose country’s ties with Syria have soured over the anti-regime revolt, later reportedly said Damascus had apologised over the downed plane.

“Syria immediately offered a very serious apology for the incident and admitted it was a mistake,” Haberturk daily newspaper quoted Erdogan as saying on a plane bound from Brazil to Turkey.

“At this moment the air force and navy are conducting search and rescue operations in the eastern Mediterranean, and luckily our pilots are alive; we have just lost a plane,” the daily quoted him as saying. There was no explanation as to why Damascus should apologise for a crash, unless its forces had shot down the Turkish F-4 or harried it.

The Syrian Observatory for Human Rights gave a higher toll for the pro-regime losses in the latest reported massacre, saying at least 26 government supporters - most of them members of the feared shabiha militia - had been killed.

In the capital, troops fired on demonstrators in the upscale district of Mazzeh, the Observatory said, without giving any immediate word on casualties.

Protesters in other areas of Damascus and its suburbs were also fired on, the Observatory said, adding that two children were shot dead in two different areas of Damascus province, although not at demonstrations.

In Syria’s third-largest city Homs, residents held a small protest despite a renewed bombardment by government forces of rebel-held neighbourhoods, activists said.

The bombardment scuppered a new Red Cross attempt to evacuate trapped civilians as the United Nations said up to 1.5 million people needed aid. It came after at least 168 were killed in violence in on Thursday, the highest single-day toll since a UN-backed ceasefire was meant to have taken effect on April 12, the Observatory said.

In the reported massacre, “armed terrorist groups ... kidnapped a number of citizens in Daret Azzeh area in the countryside of Aleppo, according to official sources in the province,” state Sana news agency said.

“The terrorist groups ... committed a brutal massacre against the citizens ... shooting them dead and then mutilating their bodies.” it added.

“Initial information indicates that more than 25 of the kidnapped citizens were killed ... with the fate of the rest of the kidnapped people still unknown.”

Amateur video posted on YouTube and distributed by the Observatory showed piles of mangled bodies of young men, their clothing soaked in blood. At least two of the bodies in the footage were wearing fatigues.

“These are shabiha of (President) Bashar Al Assad’s regime,” the narrator said, without identifying himself.

The Observatory said a total of at least 55 people were killed in violence across the country yesterday. Meanwhile, the UN Office for the Coordination of Humanitarian Affairs said up to 1.5 million Syrians now need humanitarian aid, up from the one million estimated at the end of March. “The humanitarian situation in Syria continues to deteriorate,” said the latest OCHA bulletin.

On the diplomatic front, Russian Foreign Minister Sergei Lavrov met Syrian counterpart Walid Al Muallem, urging Damascus to do more to implement the plan of peace envoy Kofi Annan.

“We called on them (the Syrian regime) to back up their declarations about readiness to implement the Kofi Annan plan with deeds,” Lavrov told state television after the meeting Saint Petersburg, Russia. “They have already done a lot but they can and must do much more.”