Both sides fighting in the ongoing battle for Syria's western city of Qusayr have been called upon by the United Nations to let trapped civilians escape the war-ravaged town.
Forces loyal to President Bashar al-Assad and rebels were warned on Saturday that they would be held accountable for the suffering of trapped civilians and that they should allow the creation of a humanitarian corridor so citizens of Qusayr could flee the violence.
International law does require fighting forces to allow aid to civilians in this sort of situation.
Qusayr is normally home to about 30,000 people.
"The eyes of the world are upon them, and they will be held accountable for any acts of atrocity carried out against the civilian population of Qusayr," a UN statement said on Saturday.
UN emergency relief coordinator Valerie Amos and High Commissioner for Human Rights Navi Pillay said they were alarmed that thousands of civilians may be trapped in Qusayr.
"We understand there may also be as many as 1,500 wounded people in urgent need of immediate evacuation for emergency medical treatment, and that the general situation in Qusayr is desperate," they said in a joint statement.
Speaking to Al Jazeera, Rupert Colville, Pillay's spokesman, said the humanitarian corridor could only be created if both sides agreed.
"Some of those wounded will clearly die if they don't get medical treatment," Colville said.
"There should be a ceasefire at least and they let the civilians and the wounded get out and also let some aid in as well. Civilians who stay behind will need food and water.
"International law does require fighting forces to allow aid to civilians in this sort of situation."
Meanwhile, six rockets fired from Syria hit Lebanon's eastern Bekaa region, a security source said. There were no casualties.
Rockets fired from Syria have repeatedly hit Lebanese territory, striking both Sunni areas that back the uprising against Assad, and strongholds of Hezbollah.
Hezbollah, which is backed by Iran and is a close ally of Assad, sent an estimated 1,700 fighters to Qusayr almost two week ago to support the regime's assault.
Its fighters encircled Qusayr as regime troops launched a fierce assault on the city.
Regime forces have recently captured the northern district of Arjun in Qusayr, leaving rebels little chance to escape.
While around 300 rebels managed on Friday to break through army lines near the village of Shamsinn, northeast of Qusayr - after losing 11 fighters - it was unclear if they could quell the advances of regime forces.
Call for arms
Brigadier General Salim Idris, the head of the military council of the Free Syrian Army, told Al Jazeera that the opposition fighters, who arrived from the northern province of Aleppo, were heavily outgunned and overwhelmed by members of the Hezbollah group.
Idris warned the "revolution could be lost", if the West did not act quickly and support the rebels with heavy weaponry.
Activists said makeshift clinics in Qusayr suffer from "acute" shortages of medical supplies.
The control of Qusayr is essential for the rebels as it is their principal transit point for weapons and fighters from across the border in Lebanon.
It is also strategic for the regime because it is located on the road linking Damascus with the Mediterranean coast, its rear base.
Assad on Thursday said he was "very confident" his regime would defeat the revolt which has raged since March 2011 at an estimated cost of more than 94,000 lives.
"There is a world war being waged against Syria and the policy of [anti-Israeli] resistance... [but] we are very confident of victory," he told Hezbollah's Al-Manar television.