A flash of a shell...

.. and an explosion in what amateur video says is a district of Aleppo in Syria.

Reuters cannot independently verify the content of these videos posted on to the internet because of government media restrictions.

But a number allegedly filmed on Saturday show fighting intensifying around the country.

Rebel fighters here in a province of Homs say they are clearing the area of Hezbollah fighters and have managed to kill some, though Hezbollah has denied sending fighters to government forces.

Meanwhile, an injured rebel fighter is carried away on a makeshift stretcher.

Scenes like these prompted a strong condemnation of the U.N. Security Council's 'inaction' by Turkish Prime Minister Tayyip Erdogan at a conference in Istanbul.

Turkey has led calls for intervention which have repeatedly been opposed by veto-wielding members Russia and China.

Erdogan called for structural changes within the organisation - and warned that it was repeating mistakes which allowed a massacre in Bosnia almost two decades ago.