Doctors and medics in two hospitals in Hodeida province said 50 people have been killed in the past 24 hours, seven of them pro-government fighters.
The bombing on a crowded market in rebel-held northern Yemen killed a total of 51 people, according to the Red Cross.
Yemen's embattled government has agreed to raise the salaries of thousands of public-sector employees, including pensioners, after hundreds of people protested in Aden against the rising cost of living.
Yemen's warring parties will not meet face-to-face at UN-brokered peace talks in Geneva this week which will likely focus on a prisoner exchange deal, government officials said Sunday.
Saudi Arabia is leading a Western-backed alliance of Arab states trying to restore the internationally recognised government of Yemeni President Abd-Rabbu Mansour Hadi.
At least 29 children were among those killed in the air raid on Thursday on a bus in a crowded market in Dahyan, Saada province, according to the International Committee of the Red Cross.
A Yemeni health official and the International Committee of the Red Cross said than an air strike had hit the bus carrying children as it drove through a market in northern Saada province.
The coalition said it had carried out what it called "legitimate military action" in the area targeting Houthi rebels.
Yemen's Houthis attacked a Saudi oil tanker in the Red Sea, causing slight damage, an Arab coalition said on Wednesday, after the Houthis reported targeting a Saudi warship in the area.
Three civilians were killed and nine wounded when a mortar shell hit a crowded market in southwestern Yemen, Doctors Without Borders (MSF) said Wednesday.
Forces backed by a Saudi-led coalition have killed eight members of Lebanon's Hezbollah group in Yemen in battles with the Iran-aligned Houthis, the coalition said on Monday.