The airstrike targeted the bus in the road between Jarahi and Zabid districts in Hudaydah, a military source, speaking on condition of anonymity, told the Saba news agency reported on Tuesday.
At least 19 civilians were killed and injured during the raid, it added.
Since June 13, the Saudi-led coalition and its mercenaries have launched massive attacks to bring the port city under their control, but have failed to achieve their objective due to Yemenis’ resistance.
The United States, Britain and France have backed the coalition in the Yemen conflict and keep providing weapons to both Saudi Arabia and the United Arab Emirates.
While the Yemeni army and popular committees are fighting off the assailants and countering attacks on residential areas, international humanitarian organizations have warned of dire consequences of any escalation of violence around Hudaydah.
UN Humanitarian Coordinator Lise Grande recently said “as many as 250,000 people may lose everything -even their lives,” if there is a military attack on Hudaydah.