A family of five from New York lost their lives in a New Year's Eve sightseeing plane crash in Costa Rica, authorities said.
Five other U.S. citizens were killed, including a Florida couple and their 19-year-old daughter.
There were no survivors after a single-engine Cessna hurtled into a mountainous area while en route to the capital city of San Jose on Sunday. Two crew members also died, bringing the death toll to 12.
Investigators were trying to determine the cause of the crash.
Bruce and Irene Steinberg, of Scarsdale, N.Y., were on vacation with their sons, Matthew, 13, William, 18, and Zachary, 19.
"We are in utter shock and disbelief right now," wrote Bruce's sister, Tamara Steinberg Jacobsen, on Facebook.
The family was on a much-anticipated trip to the Pacific Coast and then a tour through Costa Rica's lush forests and gorgeous beaches, relatives told The New York Times.
Witnesses told authorities the plane smashed into the base of a mountain not long after taking off, and appeared to flip over before impact, NBC News said.
"The government of Costa Rica deeply regrets the death of 10 American passengers and two Costa Rican pilots in the aircraft crash," Luis Guillermo Solis Rivera, the island country's president, said on Facebook.
Mitchell and Leslie Weiss, both Florida doctors, were also reportedly on the plane with the their 19-year-old daughter, Hannah, a Columbia University student. The identities of the other two Americans were not immediately released.
Though the cause of the crash remains a mystery, bad weather had prompted the Nature Air chartered plane to abort its first attempt to land in Punta Islita to pick up the Americans. The aircraft returned to another airport, then came back at about 11 a.m., according to the country's civil aviation director.
The small plane boarded the 10 Americans and then took off for San Jose, about 140 miles to the east. Images posted on Facebook by aviation officials show smoking debris strewn several hundred yards form the runway's end.
Laura Chinchilla, former president of Costa Rica, said on social media that her cousin was one the crew members killed in the crash.
Bruce Steinberg, 50, worked in investment banking and his wife, Irene, 51, was a diligent volunteer for several charitable organizations. Matthew was in 8th grade. William attended the University of Pennsylvania and Zachary went to Johns Hopkins University, according to a family friend.