The attack happened east of the city of Mukalla, the provincial capital of Hadramawt, the officials said, speaking on condition of anonymity because they were not authorized to talk to the media.
Al-Qaida's Yemen branch, considered by Washington to be the most dangerous offshoot of the terror network, has made gains in the sprawling eastern Hadramawt province, and captured Mukalla in April.
The al-Qaida offshoot has gained ground lately in Yemen, profiting from the civil war now engulfing the country.
That fighting pits Iranian-backed Shiite rebels known as Houthis and allied troops loyal to former President Ali Abdullah Saleh against an array of southern separatists, local and tribal militias, Sunni Islamic militants and loyalists of exiled President Abed Rabbo Mansour Hadi.
Washington, meanwhile, has kept up its drone attacks targeting al-Qaida militants in Yemen, including one in June in Mukalla that killed the group's top leader.
President Hadi has been living in neighboring Saudi Arabia after he and much of his government fled advances by the Houthis earlier this year.
On Wednesday, he arrived for a two-day working visit to the United Arab Emirates, one of the key backers of a Saudi-led coalition attempting to roll back gains by the rebels.
The Emirates has been participating in a Saudi-led, American-supported campaign targeting the rebels and their allies that started in March. The UAE and Saudi Arabia are widely believed to have supplied pro-government forces with tanks and other fighting vehicles.
Emirati officials have not made public the precise nature of the country's military role on the ground in Yemen. Six Emirati troops have died as part of the campaign, including three first corporals killed on Saturday. The National, a state-owned Emirati newspaper, said the most recent deaths happened in Yemen.