Worldwide rights groups have accused the Saudi-led coalition of bombing civilian gatherings, markets, hospitals, and residential areas across Yemen since the beginning of its campaign against Houthi rebels in 2015.
The deaths also highlight the security challenges that aid organizations face in Yemen, the United Nations agency said, adding that it was "deeply shocked and saddened" by the incident.
"Preliminary reports are that the IDP (internally displaced) families were trying to flee hostilities from elsewhere in Taiz", a spokesperson said.More news: Ravi Shastri to pick the core staff
Yemen's defenseless people have been under massive attacks by the coalition for more than two years but Riyadh has reached none of its objectives in Yemen so far.
The coalition, backed by the U.S., initially launched an aerial bombing campaign against Shiite Houthi rebels in March 2015 followed by a ground operation. However, they "continue to be exposed to danger as the conflict has affected all of Yemen's mainland governorates", UNHCR said in its statement Tuesday.
"This latest incident once again demonstrates the extreme dangers facing civilians in Yemen, particularly those attempting to flee violence, as they disproportionately bear the brunt of conflict", UNHCR said.More news: Notorious 86-year-old jewel thief Doris Payne arrested again - at Walmart
The Saudi-led coalition has faced repeated criticism over civilian casualties in Yemen.
"The coalition claimed that the security of the journalists could not be guaranteed in rebel-controlled areas and advised the three journalists to travel on commercial flights", said Ahmed Ben Lassoued, a spokesman for the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) in Yemen. "UNHCR, as the lead agency for protection under the coordinated humanitarian response in Yemen, has been appealing to parties to the conflict to ensure their utmost in the protection of civilians and the mitigation of suffering".
The Saudi coalition has placed an air and sea blockade on Yemen as it fights a war against the Houthi rebel movement, and effectively controls the country's airspace.More news: Ed Sheeran to have a 'thing' with Lisa Simpson
Saudi Arabia is using British-manufactured weapons in the offensive, sparking failed legal challenge by the Campaign Against the Arms Trade in the High Court.