A limousine involved in a crash that killed 20 people in upstate New York yesterday failed to stop at an intersection seconds before the collision.

New York State Police First Deputy Superintendent Christopher Fiore confirmed that all 18 people in the limousine were killed, as well as two bystanders.

Fiore said the 2001 Ford Excursion limousine was traveling southwest on state Route 30 in Schoharie, about 170 miles north of New York City and 43 miles west of Albany, when it went through the intersection with Route 30A and struck a parked 2015 Toyota Highlander outside the Apple Barrel Country Store.

An aunt of one of the victims said the limousine was on its way to a birthday party when it crashed.

Valerie Abeling said newlyweds Erin Vertucci, 34, and Shane McGowan, 30 were among those killed. Abeling added that her daughter had been invited along but was unable to go.

National Transportation Safety Board Chairman Robert Sumwalt said it was the deadliest transportation-related accident in the U.S. since February 2009, when 50 people were killed after a Continental Airlines regional flight crashed into a house near Buffalo, N.Y.

“My heart breaks for the 20 people who lost their lives in this horrific accident on Saturday in Schoharie,” New York Governor Andrew Cuomo said in a statement. “I commend the first responders who arrived on the scene and worked through the night to help. State police are working with federal and local authorities to investigate the crash, and I have directed State agencies to provide every resource necessary to aid in this investigation and determine what led to this tragedy.”

“I join all New Yorkers in mourning these deaths and share in the unspeakable sorrow experienced by their families and loved ones during this extremely difficult time,” Cuomo said.

Sumwalt said an NTSB go-team arrived in the area this morning to investigate the cause.

The crash “sounded like an explosion,” said Linda Riley, of nearby Schenectady, who was on a shopping trip with her sisters and had been in their parked car at the time at the store, which sits near the T-junction of Routes 30 and 30A.