SAN JOSE, Costa Rica (CBS/AP) – A University of Pennsylvania student and his family were among the 12 people killed in a small plane crash in Costa Rica on Sunday.

University officials confirmed Monday that William Steinberg, a freshman at Penn, and his family were on board the plane when it crashed in a wooded area in Guanacaste, northwest Costa Rica soon after takeoff.

A family in the suburbs of New York City identified the victims 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.

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.

Another family with ties to the Philadelphia area was also killed in the crash. Officials confirmed that physicians Mitchell Weiss, his wife Leslie, and their two teenage daughters were  on board when the plane went down. The family relocated from Plymouth Meeting to Belleair, Florida in 2005.

Costa Rican investigators continue to look into what caused the charter aircraft to crash, killing the 10 U.S. citizens and two local crewmembers on board.

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.

Cubillo identified the pilot as Juan Manuel Retana and described him as very experienced. Former Costa Rican President Laura Chinchilla said via 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 immediately respond to phone and email messages.

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