Two people taken to Christiana Hospital after collision Friday afternoon just south of the Route 299 overpass.

Delaware State Police are still investigating a collision involving multiple vehicles on Route 1 Friday afternoon near Middletown, about 2:40 p.m., just south of the Route 299 overpass.

A 2001 GMC Yukon, driven by a 76-year-old Pennsylvania man, was traveling south in the left lane of Route 1 and was slowing due to heavy traffic.

The Yukon was rear-ended by a 2018 Chevrolet Suburban, driven by a 51-year-old Pennsylvania man, causing the Yukon to become airborne, roll over, and then spin several times before striking the right rear side of a 2016 Jeep Wrangler that had been slowing ahead of the Yukon in the southbound lane.

The driver of the Yukon sustained serious but non-life threatening injuries and was transported to Christiana Hospital. His passenger, a 77-year-old woman, suffered serious injuries and was flown to Christiana Hospital by a state police helicopter.

The driver of the Wrangler, a 52-year-old Pennsylvania man, did not report any injuries.

The driver of the Suburban and his 57-year-old female passenger did not report any injuries.

The driver of the Suburban told police that traffic stopped abruptly in front of him and he swerved to the left in an attempt to avoid a collision. This driver was issued a citation for following a motor vehicle too closely.

The chain-reaction collision affected traffic flow for several hours until the injured people were treated, the vehicles were cleared and police investigated.