Two trucks carrying food and medical supplies into rebel-held neighbourhoods in the central Syrian city of Homs turned back under heavy fire, leaving four paramedics wounded as a ceasefire faltered.

Tens of thousands of defiant Syrian protesters have thronged the streets of Homs calling for the execution of president Bashar Assad after his Arab League monitors were allowed in the city for the first time.

Syrian security forces fired tear gas and live ammunition at anti-government protesters who took over a main square in the country's third-largest city today, witnesses and activists said.

Masked militiamen shot three alleged Palestinian informers for Israel in a West Bank town square today, and a large crowd quickly gathered to watch the wounded men writhing on the ground in pain.