UNITED NATIONS - UN Secretary General Ban Ki-moon has called for an immediate end to “hostilities” in Yemen amid a rise in the number of civilian fatalities caused by Saudi-led military coalition’s airstrikes.

In a statement released on Wednesday, the secretary-general asked “all parties to the conflict to immediately cease all hostilities and for the Yemeni parties to return to direct talks facilitated by his special envoy for Yemen.”

The coalition has stepped up its air raids in Yemen, especially Sana’a, ever since peace talks in Kuwait between representatives of the Saudi-backed former government and Houthis were suspended on August 6. The UN chief reminded all parties “of the utmost necessity to protect civilians and to respect their obligations under international humanitarian law.” Ban further condemned the loss of at least nine civilian lives in a recent Saudi aerial attack against the Nihm district east of the Yemeni capital, Sana’a, but he did not name the kingdom in his criticism. “Civilians, including children, are paying the heaviest price in the ongoing conflict, as civilian infrastructure, such as schools and hospitals, continue to be hit,” he said.

The attack came less than 48 hours after Medical aid group Doctors Without Borders (MSF) said Saudi airstrikes on a school in the northern province of Sa’ada had killed 10 children. The UN chief has already taken flak for dropping Saudi Arabia from a list of children’s rights violators after coming under “undue pressure.”

On Wednesday, Saudi Arabia kept on attacking new positions across Yemen. Yemeni reports said warplanes had carried out nearly 50 airstrikes against various neighbourhoods across the Sa’ada province in a span of 24 hours.

At least three people lost their lives and eight others sustained injuries on Wednesday evening when a Saudi jet struck a residential building in Majz district.

Saudi warplanes also launched two airstrikes against the Kahlan military base, and another against non-operational Sana’a International Airport. Furthermore, Saudi aircraft struck Sahar and ?aydan districts in Sa’ada Province.

According to UN, the conflict in Yemen has damaged or demolished more than 70 health centers, including three MSF facilities.

Saudi Arabia and its allies intervened in support of exiled Yemeni government in 2015, but have failed to bring it back to power.

The war and airstrikes in Yemen have since killed over 6,400 people, mostly civilians.

AFP adds: An Al-Qaeda suicide bomber killed four Yemeni soldiers in an attack Thursday in the southern Abyan province, where government forces have launched an anti-jihadist offensive, a military official said.

The attacker rammed his car into two military vehicles parked on a road linking the towns of Loder and Moudia in Abyan province, the source said.

“Four soldiers were killed and others were wounded,” the official told AFP.

The attack came after troops recaptured both towns from the jihadists who fled to surrounding mountains as the army entered, residents said.

Military sources said the bombing was a retaliation attack by Al-Qaeda after government troops recaptured parts of Abyan, including provincial capital Zinjibar.

Government forces, backed by air power from a Saudi-led coalition, launched the offensive to retake Abyan on Sunday, after they failed to recapture the vast province earlier this year.

Al-Qaeda and Islamic State group jihadists have exploited a power vacuum in Yemen to expand their presence in the country’s south and southeast.

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Yemeni authorities had trained hundreds of soldiers in the nearby province of Aden over the past two months to retake Abyan.

The Arab coalition, which intervened against Iran-backed rebels in March last, began supporting the government’s war on jihadists this year.

The United States has also pressed a drone war against them.

Washington considers the Yemen-based Al-Qaeda in the Arabian Peninsula, or AQAP, to be the extremist network’s deadliest franchise.