Updated at 9:55 p.m. ET

The Costa Rican government says a plane crash in Costa Rica on Sunday has killed all 12 people aboard.

The aircraft was carrying 10 American tourists and two Costa Rican pilots when it came down in the mountainous region of Punta Islita, about 140 miles west of its destination, the capital of San José. The cause of the crash is not yet known.

Reuters reports:

"There are no people alive," Security Minister Gustavo Mata said, adding that autopsies would be needed to confirm the total number and identities of victims because their remains were badly burned.

The AP adds:

At a news conference, Enio Cubillo, director of Costa Rica Civil Aviation, said the Nature Air charter flight took off just after noon Sunday from Punta Islita and was headed for the capital of San Jose when it crashed.

Cubillo said the same plane was delayed in arriving that morning in Punta Islita from San Jose due to strong winds.

He also described the pilot, Juan Manuel Retana as very experienced. Former Costa Rican President Laura Chinchilla said on Twitter that Retana was her cousin.

In a statement on social media, President Luis Guillermo Solís expressed his sorrow and promised full support for the victims' families "in this difficult moment." All emergency services are on call, he added. Authorities will begin investigating the crash starting tomorrow, the president said.

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