Flowers and tributes, to the victims and injured, continue to adorn the Place de la Bourse following yesterday's terrorists attacks on March 23, 2016 in Brussels, Belgium. 
Photo by Christopher Furlong/Getty

New York-based Sascha, Alexander Pinczowski killed in Brussels blasts

Updated

BRUSSELS — A New York-based brother and sister were among those killed during this week’s Brussels attacks, a person with knowledge of the situation confirmed Friday.

Sascha and Alexander Pinczowski had just arrived at the Brussels Airport when two explosions went off Tuesday. They had not been seen since, but on Friday they were confirmed as having died in the twin blasts.

A person with knowledge of the situation told NBC News in an email that an “identity match” had been confirmed for “both Alex and Sascha, so we can now lay them to rest.”

The siblings had been due to fly home to New York at the time of the blasts.

Delta also confirmed Friday that some of its passengers were among those fatally injured in the departures area.

At least 31 people died and more than 270 were wounded in the explosions at the airport and another blast an hour later at a metro station. ISIS has claimed responsibility.

Earlier on Friday, a senior U.S. official told NBC news that two Americans had been confirmed killed in the attacks, without giving their identities.

Two other Americans, Justin Shults and his wife Stephanie, have not been heard from since the attacks, family members have said.

This article originally appeared on NBCNews.com.

Brussels and ISIS

New York-based Sascha, Alexander Pinczowski killed in Brussels blasts

Updated