"The air force bombed a gathering of fighters in the region of Harib believing them to be Houthis," a military source said, AFP reported on Friday.
A tribal chief confirmed the overnight strike, saying that those killed appeared to be local tribesmen fighting on the side of the forces loyal to Mansour Hadi.
Harib is around 80 kilometres (50 miles) south of Ma'rib, the capital of the central province.
Hadi loyalists, backed by the Saudi-led coalition, claim they are advancing on the ground in Ma'rib as part of a major offensive against Houthis, who control large parts of the country.
Coalition aircraft launched a series of raids Friday morning on Houthi positions in the south of the province, military sources said.
The United Nations says nearly 4,900 people have been killed and around 25,000 wounded since late March, while 21 million out of Yemen's population of 25 million have been affected by the conflict.