Two trucks carrying food and medical supplies into rebel-held neighbourhoods in the central Syrian city of Homs have turned back under heavy fire, leaving four paramedics wounded as a ceasefire faltered, officials said.
Talal Barrazi, the governor of Homs province, told the Lebanon-based Al-Mayadeen TV that the attack occurred late in the afternoon and that the trucks were targeted by two roadside bombs and a mortar shell from the rebel side.
Homs activist Ahmad al-Qusair however denied there had been roadside bombs and said the convoy was attacked by mortar shells fired by government forces.
Mr Barrazi later told Syrian state TV that two trucks were able to reach opposition-held neighbourhoods earlier in the day. Al-Mayadeen also reported that two trucks, carrying 250 food parcels, were able to cross into rebel-held areas.
The state TV said four members of the Syrian Arab Red Crescent were wounded by rebel fire in the area but gave no further details.
The Syrian Arab Red Crescent said on its Facebook page that its members were able to deliver 250 food parcels and 190 parcels containing detergents and medicines to the central neighbourhood of Hamidiyeh despite being targeted by several mortar rounds. It added that one of its members was lightly wounded and two trucks were damaged.
It was not immediately clear why state media said four paramedics were wounded and the Red Crescent said only one.
Mr Barrazi said about 100 civilians expected to be evacuated from rebel-held areas had yet to arrive. Yesterday, 83 children, women and elderly people on wheelchairs were evacuated from Homs, the first people to leave the area in months, the UN said.
Syrian forces loyal to President Bashar Assad have prevented the entry of food and medical aid into rebel-held parts of the city for over a year, badly affecting hundreds of civilians holed up in the areas. An agreement had called for a three-day truce to allow the evacuation of some civilians and the entry of food shipments.
Al-Mayadeen aired live footage from the city's Clock Square showing two white trucks identified with Syrian Arab Red Crescent markings as they returned from their unfulfilled mission. The station's reporter in the area said the radiator of one of the trucks was hit by a bullet.
"After the vehicles drove about 200 meters (yards) two roadside bombs went off, and when they kept going a mortar round fell in the area coming from the direction of Hamadiyeh," said Mr Barrazi, referring to a rebel-held central neighbourhood.
Earlier in the day, a Syrian official said fighting had broken out and that a mortar shell had landed near UN personnel. An activist said combat began when government forces fired 11 rockets toward the rebel-held Hamidiyeh quarter.
The Britain-based Syrian Observatory for Human Rights said two people were killed and several others wounded in an attack on rebel-held neighbourhoods that residents blamed on government forces.
Homs city was one of the first areas to rise up against Assad in 2011 and has been particularly hard hit by the war. Over the past year, the government has regained control over much of the city, except for a few neighbourhoods in the historic centre.
A coalition of exiled Syrian activists said they feared the agreement would be used as a "prelude to the regime destroying the city".
"It has used similar deals to buy time to strengthen its positions on the ground and to kill more civilians," the Syrian National Coalition said.