"A convoy of tribesmen fighting alongside with the Saudi-backed government forces was mistakenly hit by air raids in Harib region of Marib province, killing at least 15 people and injuring 10," Xinhua news agency quoted a military official as saying.
"The incident occurred after scores of tribal fighters moved into the battlefield to fight Houthi gunmen, but a friendly fire targeted their cars mistakenly while travelling on a desert road," the military source said.
Fierce fighting continued between Houthi gunmen and Saudi-backed government forces on Friday in different areas in Marib, Yemen's most important oil-producing province, 170 km from here.
Soldiers of the United Arab Emirates and Qatar supported by armoured vehicles were engaged in battles against Houthis in Marib, according to local sources.
Yemen has been engulfed in the war between the Shiite Houthi group supported by army units loyal to former President Ali Abdullah Saleh and the Saudi-backed government forces.
In late March, the Saudi-led coalition began airstrikes against the Houthi group in Yemen at the request of exiled Yemeni President Abd-Rabbu Mansour Hadi.
The campaign aims to prevent the Houthis from seizing power in Yemen, as Saudi Arabia claimed the Shiite group is backed by Iran.