DAMASCUS, Syria (AFP) — The Syrian army said yesterday it has seized the last rebel-held district of the capital as insurgents in the strategic northern city of Aleppo came under heavy bombardment by regime forces.

The army said it had retaken the hold-out rebel district of Tadamun in Damascus, a day after the United Nations deplored the failure of diplomacy to end a conflict that has reportedly claimed more than 21,000 lives in nearly 17 months.

A brigadier general who refused to give his name told journalists visiting the neighbourhood of Tadamun, the scene of heavy fighting earlier, that it has been retaken, and that the military now controls all of the capital.

"We have cleansed all the districts of Damascus, from Al-Midan to Mazzeh, from Al-Hajar Al-Aswad to Qadam... to Tadamun," the last rebel bastion in the capital, said the officer.

An anti-regime activist, Lena al-Shami, told AFP in Beirut by Skype that the rebel Free Syrian Army (FSA) had withdrawn from Tadaman and would focus on "hit-and-run tactics against important regime targets".

Tadamun borders the Palestinian refugee camp of Yarmuk and is home to both Syrians and Palestinians. It is now deserted and devastated, with electricity cables hanging down between rooftops and paving badly damaged.

In Yalda next to Tadamun, an AFP reporter saw a dozen corpses thrown on a rubbish dump. Some had been burned and others mutilated.

Fighting erupted in Damascus on July 15 and raged for several days as rebels seized several districts, forcing thousands of residents to flee.

In Aleppo, Abdel Jabar Oqaida, commander of the FSA there, said the Salaheddin district had "come under the heaviest bombardment since the battle began" on July 20 but that loyalists had "not managed to advance".

A senior Government security figure warned that "the battle for Aleppo has not yet begun, and what is happening now is just the appetiser... The main course will come later".

The official said more reinforcements had arrived and that at least 20,000 troops were now on the ground. "The other side are also sending reinforcements," the official added of the rebels, who claim to have seized half the city.

Because of restrictions on the free movement of journalists in Syria, none of the claims can be verified.