The market was used to sell vegetables and khat, the narcotic leaves widely consumed in Yemen and the Horn of Africa. It was hit during its busiest time, around 8 a.m., said Tawfeeq Al Sufi, a relative of one of the victims.
Mr. Sufi said that shrapnel struck his cousin in the abdomen. “Right before he bled out,” he said, “ he gave someone his cellphone and said, ‘Call my family and tell them I died.’ ” The man had a wife and four children, Mr. Sufi said.
The other attack struck a farm in Al Hudaydah, a province further west, and killed 14 members of one family. The Saudis believe Iran is smuggling weapons to the rebels through Hudaydah — a claim that remains largely unsubstantiated.
“These incidents prove the complete disregard for human life that all parties, including the Saudi-led coalition, continue to show in this absurd war,” Jamie McGoldrick, the United Nations aid coordinator in Yemen, said in a written statement, adding that he was “deeply disturbed” by these attacks.
“There can only be a political solution,” he said, urging both sides in the war to abandon their “futile military campaign.”
Mr. McGoldrick’s statement did not confirm the Yemeni account that the airstrikes had been carried out by the Saudi-led coalition, but it did remind all sides, including the coalition, to “always distinguish between civilian and military objects.”
The market was not near any permanent rebel military installations, but it was close to the site of recent clashes between Houthis and pro-government forces. It remains unclear whether the farm was near any military targets. The United Nations and international aid groups have accused the Saudi-led coalition of repeatedly attacking civil gatherings and residential areas.
Saudi officials vehemently deny this, and the United States supports their campaign in Yemen.
A spokesman for the Saudi-led coalition could not be immediately reached for comment on Thursday.
The civil war in Yemen has killed an estimated 10,000 people and displaced at least three million. Much of the country’s infrastructure and health system has been destroyed by coalition airstrikes and rebel shelling.
Yemenis suffer from dire shortages of electricity, food and medicine. The collapse has led to the world’s worst contemporary outbreak of cholera, which has killed over 2,200 and affected about a million people since April.
The death of Mr. Saleh — who became a strong ally of the Houthis, but was killed after publicly breaking with them — has further exacerbated the humanitarian crisis, local and United Nations officials said.
The Saudi-led coalition has attempted to capitalize on his death by increasing its airstrikes to roughly 120 a day nationwide from about 80. The Houthis, meanwhile, have responded with a crackdown in the areas they control, arresting hundreds for real or imagined ties to Mr. Saleh, blocking the entry of humanitarian aid and shutting off access to the internet.