The Ministry of Defence said in a text message that some of the dead militants had been senior military leaders of Ansar al-Sharia, which has close links to the Yemen-based al Qaeda in the Arabian Peninsula (AQAP).
Earlier in the day, a Yemeni aid worker for the International Committee of the Red Cross was killed by an air strike in the province while carrying out humanitarian work, the agency said.
A local official told Reuters on Wednesday that the ICRC worker had been killed in a strike by the Yemeni air force.
Yemen is several weeks into a US-backed offensive against militants who seized territory in the south last year during an uprising that forced president Ali Abdullah Saleh to step down.
President Abd-Rabbu Mansour Hadi, who took office in February in a power transfer brokered by Saudi Arabia and blessed by Washington, has sworn to stamp out AQAP, which has plotted attacks abroad.