Fighting in Yemen over the past few weeks has killed more than 540 people and wounded 1,700 as the country sinks deeper into a multi-sided conflict, the World Health Organization said Tuesday.
"More than 540 people have been killed and some 1,700 others wounded by the violence in Yemen since 19 March," a WHO spokesman said. A UNICEF spokesman said at least 74 children have been killed and 44 wounded since March 26.
UNICEF said the violence has disrupted water supplies in areas of southern Yemen and that sewage is overflowing in some locations, raising the risk of disease outbreak.
Hospitals are struggling to treat large numbers of wounded with insufficient supplies and some medical facilities have come under attack, the agency. It said at least three health workers, including an ambulance driver, have been killed in attacks.
Children are especially vulnerable, said the agency's Yemen representative, Julien Harneis.
"They are being killed, maimed and forced to flee their homes, their health threatened and their education interrupted," Harneis said in a statement, released Monday in Amman, Jordan.
The fighting pits allies of the country's embattled president, Abed Rabbou Mansour Hadi, against Shiite rebels known as Houthis and their allies, military units loyal to Hadi's predecessor, ousted autocrat Ali Abdullah Saleh.
A Saudi-led coalition, which supports Hadi, has been carrying out airstrikes targeting the Houthis and their allies to halt their advance on Aden, Yemen's second-largest city.
On Tuesday, loyalist forces backed by Saudi-led naval shelling thwarted a new rebel assault in Aden as medics and officials reported 18 dead in fighting across the south.
Militia loyal to Hadi battled rebels attempting to advance on a port in the city's Mualla district, witnesses said.
Four loyalist militiamen were killed and 12 wounded, a medic at a military hospital told AFP.
Six Shiite Houthi rebels were killed, an army source said.
Residents said that the loyalists had pushed the rebels further from the port, as warships of the Saudi-led coalition shelled rebel positions across Aden.
Mualla is not Aden's main port but it has been the focus of fierce fighting in recent days. On Monday, medics and officials said 53 people had been killed in fighting in the area over the previous 24 hours.
In Abyan province further east, armed tribesmen loyal to Hadi killed eight rebels in an attack on their convoy, provincial governor El-Khedr al-Saeedi said.
He said that loyalist tribes and militia in Abyan and neighboring Lahej province were sending fighters to Aden to back Hadi's forces in the city.
Houth military sources said five bombs were also dropped on the Republican Guard base near the city of Ibb, 160 km (100 miles) south of the capital Sanaa, apparently targeting air defense units and soldiers' quarters.
They said the commander of the base was wounded. The september26 website said two students were killed, while the Houthis' Maseerah television reported three student deaths.
During the night, Saudi-led warplanes carried out fresh strikes on the rebel-held Al-Anad air base in Lahej province, pro-Hadi General Muthanna Jawas said.
The fighting raised doubts over the possibility of landing ground forces from the Saudi-led coalition to carve out an enclave to which Hadi, who fled the country two weeks ago, could return.
"Conditions are very dangerous right now," UNICEF's Dr. Gamila Hibatullah in Aden was quoted as saying. "Hospitals are overflowing, and even ambulances have been hijacked."
Water systems have been repeatedly damaged in three southern systems, including Aden, the agency said, adding that it is providing fuel for pumping water. It said that in other southern areas, there are reports of water accumulating in the streets and sewage overflowing.
The agency estimated that more than 100,000 people have left their homes in search of safer areas.
Meanwhile, the International Committee of the Red Cross aims to fly two planes carrying a total of 48 tons of medical help and other aid to Yemen over the next two days.
Delivery of the aid shipments has been repeatedly held up as the ICRC negotiated clearance with the Saudi-led coalition which has mounted airstrikes on Yemen's Houthi fighters for nearly two weeks. It also struggled to find aircraft to fly into Yemen.
ICRC spokeswoman Marie Claire Feghali said it planned to fly the first plane, which is loading up in Jordan with 16 tonnes of medical aid, to Yemen Wednesday.
The second, carrying medical aid and other equipment including tents and generators, is being prepared in Geneva and will fly to Yemen Thursday, she said.
Both flights have been cleared with the Saudis.
Feghali said the Red Cross was still trying to get clearance for a boat to bring a team of surgeons from the ICRC and the medical aid group Medecins Sans Frontieres to Aden from Djibouti.
