Updated

Marion Van Reeth biked hundreds of miles through rugged parts of the world on charity excursions. It was a family vacation cycling outing in New York that left the Belgian airline executive with the most severe injuries of anyone who survived this week's terrorist truck attack — her legs so badly mangled they had to be amputated.

Van Reeth's husband, Aristide Melissas, and their 16-year-old son, Daryl Melissas, were also among the dozen people hospitalized after Tuesday's attack on a lower Manhattan bike path that took eight lives — six of them foreign visitors. The couple's nephew, who was part of their group, suffered only scratches and did not need to be hospitalized.

The family's situation was confirmed by a Belgian government official in New York who insisted on anonymity and said the family had issued strict instructions that they wanted to be left in private.

In initial reports from New York authorities after Tuesday's attack, Van Reeth, 54, was listed as having suffered "massive trauma to both legs" that left her life in danger. Her husband and son suffered head and neck injuries.

In part because of the family's request for privacy, details about them have been slow to emerge, though some information can be found on social media.

They live in Antwerp, where Daryl attended high school and his father, 47, has worked as an executive for a plastics company founded by his family in 1948.

As for Van Reeth, web pages for Brussels Airlines list her as its marketing communications manager who also participated in the company-sponsored Bike for Africa charitable program. A participant page with her smiling photo lists her as having been a part of the charity's first three cycling expeditions — to Rwanda and Burundi in 2011, to Uganda in 2014, and to Senegal and Gambia in 2016.

Prior to that last trip, she wrote on Bike for Africa's website that she looked forward to "a new and motivating challenge" meeting local residents and supporting charity projects.

A spokesman for the airline, Wencke Lemmes, declined to respond to an emailed inquiry about the family. He referred the inquiry to Belgium's Foreign Ministry, which did not immediately reply to a telephone message.

The Belgian field hockey association, after learning of the family's injuries, posted a message on Facebook noting that Aristide Melissas had played for one of its senior-level teams in the Antwerp area. The message expressed support "on behalf of the entire great hockey family" of Belgium.

The list of seriously injured also includes Martin Marro, 48, a resident of the Boston area and native of Argentina who lost five friends in the attack. The group had traveled to New York on a trip to celebrate the 30th anniversary of their graduation from a high school in Argentina.

Marro, initially listed in critical condition, is expected to recover fully from his injuries, his family said in a statement Friday. He is a researcher for pharmaceutical firm Novartis in Cambridge, Massachusetts, company spokesman Ryan McBride said.

Other Argentinians who survived the attack visited Marro in the hospital late Thursday to tell him for the first time that his friends had been killed.

"Martin had to know the truth. Maybe he already imagined that, but now he knows, and it is a step that his friends wanted to take before returning to Argentina," Argentina's consul in New York, Mateo Estreme, told reporters in Spanish. "It was something very emotional for all of them."

Among those shaken up but not seriously hurt in Tuesday's attack was Noah Salz, a 17-year-old who was on a school bus that was T-boned by the attacker's rented Home Depot pickup truck.

"I heard a loud crash sound, and the bus matron landed right on me," Noah told WABC-TV. "I started to cry, and then I said, 'I just want to get out of here as quickly as I can.'"

City Schools Chancellor Carmen Fariña said the Brooklyn teen returned to school the next day because he didn't want to disrupt his record of perfect attendance.