A Saudi-led coalition pounded rebels in southern Yemen Saturday and dropped more arms to loyalist fighters as the UN Security Council prepared to discuss calls for "humanitarian pauses" in the air war.
Yemen's main southern city, a last foothold of supporters of absent President Abd-rabbo Mansour Hadi, has been shaken by more than a week of fierce clashes between Shia rebels and loyalist militia.
Coalition war planes and ships bombarded Shia Houthi rebel positions in Aden.
A military source said at least 13 rebel fighters were killed.
For a second night, the coalition airdropped weapons and ammunition to supporters of Hadi, who fled to Saudi Arabia late last month as the Houthis approached his refuge.
Pro-Hadi fighters were seen unpacking rifles from wooden crates dropped by parachute.
"We thank the kingdom of Saudi Arabia and all the Gulf countries, as well as our brothers in Arab countries, for dropping supplies," said Ahmad Qassem al-Shaawi, a local militia chief.
"God willing, we will be victorious and bravely carry on fighting as heroes, and fight off any attack."
Aided by the strikes and arms drops, the pro-Hadi fighters have managed to drive the rebels back from some parts of central Aden including Hadi's palace.
At least 185 dead and 1,282 wounded from the clashes have been counted in hospitals in Aden since March 26, the city's health department director Al-Kheder Lassouar said.
Three-quarters were civilians, he added.
The toll does not include casualties among the Huthi Shiite rebels and their allies, who do not take their casualties to public hospitals, or victims of air raids, he said.
Lassouar called on international organisations and Arab states participating in the coalition to provide emergency medical assistance to hospitals in Aden.
"Medicine stocks are exhausted and hospitals can no longer cope with the increasing number of victims," he said.
Yemen, an impoverished state on the southern tip of the Arabian Peninsula, is the scene of the latest proxy struggle playing out between Middle East powers, after Syria and Iraq.
Iran, which backs the Huthis, has accused Sunni-ruled Saudi Arabia of sowing instability in the region.
But it has rejected as "utter lies" accusations that it armed the rebels, who have allied with army units loyal to former president Ali Abdullah Saleh.
The United Nations said on Thursday that 519 people had been killed and nearly 1,700 injured in two weeks of fighting around the country.
The UN Security Council was to meet later on Saturday to discuss a Russian proposal for humanitarian pauses in the air war, now in its 10th day, diplomats in New York said.
The Red Cross said hospitals in Aden were overwhelmed by the casualties and fighting was making it nearly impossible for aid workers to move around
Two brothers working for the Yemen Red Crescent Society were shot dead on Friday in the southern city while evacuating the wounded, it said.
"In Yemen, we are seeing Red Crescent volunteers being deliberately killed as they strive to save others. This is the third senseless death in a single week. This is a very worrying trend and a tragic loss," said Robert Mardini of the International Committee of the Red Cross.
The turmoil has allowed Al-Qaeda to expand its foothold in the southeast of the deeply tribal country, which had been a key US ally in the war on the extremist network.
On Friday, Al-Qaeda fighters captured the regional army headquarters in Mukalla, capital of the southeastern province of Hadramawt.
They now control nearly all of the city, where they stormed a jail and freed 300 inmates on Thursday.
In the southern town of Daleh, the Huthi rebels broke into a jail and freed more than 500 prisoners, according to a military source, who voiced fears of "widespread anarchy" engulfing the country.