'There are no people alive': Costa Rica plane crash kills all 12 on board

Costa Rican investigators are looking into what caused a charter aircraft to crash in woods in the country's northwest soon after takeoff, killing the 10 U.S. citizens and two local crew members on board.

Cause of crash that left 10 Americans and 2 local pilots dead not yet known

People stand at the site of a plane crash near Punta Islita, Guanacaste, Costa Rica, Sunday. Twelve people died, 10 of whom were American citizens. Two were Costa Rican crew members. (Costa Rica's Public Safety Ministry via The Associated Press)

Costa Rican investigators are looking into what caused a charter aircraft to crash in woods in the country's northwest soon after takeoff, killing the 10 U.S. citizens and two local crew members on board.

Officials said Sunday evening that they were still seeking to establish the names of the Americans who died when the plane went down at midday in Guanacaste. They said Nature Air had provided a passenger list, but the names on it had not been confirmed.

"There are no people alive," Costa Rica's 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.

A family in the suburbs of New York City said five of the dead Americans were relatives on vacation. They identified them as Bruce and Irene Steinberg and their sons Matthew, William and Zachary, all of Scarsdale.

"We are in utter shock and disbelief right now," Bruce Steinberg's sister, Tamara Steinberg Jacobson, wrote on Facebook. She also confirmed the deaths in an interview with NBC News.

Smoke rises from the site of a plane crash in Punta Islita, Guanacaste, Costa Rica, Sunday. A government statement said the plane belonged to Nature Air and had taken off nearby. (The Associated Press)

Rabbi Jonathan Blake of the Westchester Reform Temple in Scarsdale said in a statement posted on the temple's Facebook page and emailed to The Associated Press that the Steinbergs were involved in philanthropy and local Jewish groups. "This tragedy hits our community very hard," Blake wrote.

At a news conference, Enio Cubillo, director of Costa Rica Civil Aviation, said the Nature Air charter flight crashed shortly after taking off just after noon Sunday from Punta Islita on a planned flight to the capital of San Jose. He said investigators were looking into possible causes.

Cubillo identified the pilot as Juan Manuel Retana and described him as very experienced. Laura Chinchilla, who was president of Costa Rica from 2010 to 2014, said on Twitter that Retana was her cousin.

The same plane had arrived in Punta Islita on Sunday morning from San Jose and was delayed in landing by strong winds, Cubillo said.

Nature Air did not respond to phone and email messages.

With files from Reuters