Kathmandu, Nepal (CNN) -- A DeHavilland DHC-6 Twin Otter aircraft that went missing en route from Lamidanda to Kathmandu in eastern Nepal crashed in a mountainous area east of the capital, killing all 22 people aboard, an airport spokesman said Thursday.
"The aircraft seems to have hit a mountainside," Purusottam Shakya, operations supervisor at Tribhuwan International Airport, which serves Kathmandu, told CNN.
The plane disappeared Wednesday, and search and rescue teams looked for it until night fell. A search team in a helicopter found pieces of the aircraft Thursday morning about 150 kilometers east of Kathmandu, said Shakya.
Lamidanda is about 200 kilometers east of Kathmandu.
Shakya said the plane carried 19 passengers -- including one U.S. national -- and three Nepalese crew members. The other 18 passengers were Nepalese.
In August, 14 people were killed when a plane crashed in central Nepal.