ADDIS ABABA, Ethiopia — An Ethiopian Airlines flight with 157 people thought to be on board crashed shortly after takeoff Sunday morning from Ethiopia's capital headed to Nairobi, the airline said.

The airline's statement said 149 passengers and eight crew members were thought to be on board the Boeing 737 that crashed six minutes after takeoff just south of Addis Ababa, on its way to Kenya's capital.

While the airline said that "search and rescue operations are in progress and we have no confirmed information about survivors or any possible casualties," a separate statement by the Ethiopian prime minister's office offered its "deepest condolences" to families.

There were no immediate details on what caused the crash.

The state-owned airline is one of the biggest carriers on the continent by fleet size. It said previously that it expected to carry 10.6 million passengers last year.

Its last major crash was in January 2010, when a flight from Beirut went down shortly after take-off.

Sunday's crash comes as the country’s reformist prime minister, Abiy Ahmed, has vowed to open up the airline and other sectors to foreign investment in a major transformation of the state-centered economy.