Dale Earnhardt Jr. starts 12-car wreck at Daytona, essentially shutting down 3-day test

abe6b68e-NASCAR Daytona Testing Auto Racing

Jamie McMurray, right, watches as crew members make adjustments to his car in his garage during NASCAR auto race testing at Daytona International Speedway, Friday, Jan. 11, 2013, in Daytona Beach, Fla. (AP Photo/John Raoux) (The Associated Press)

34bcb9a6-NASCAR Daytona Testing Auto Racing

A pack of cars drives past the start/finish line moments before a wreck on the backstretch during NASCAR auto race testing at Daytona International Speedway, Friday, Jan. 11, 2013, in Daytona Beach, Fla. (AP Photo/John Raoux) (The Associated Press)

DAYTONA BEACH, Fla. – Dale Earnhardt Jr. started a 12-car accident at Daytona International Speedway that essentially shut down a three-day test session.

NASCAR's most popular driver tapped Marcus Ambrose as they drove across the back straightaway, lifting him "like a forklift" and turning him into the wall. Ambrose's car bounced back across the track and collected a host of others.

Two of Earnhardt's Hendrick Motorsports teammates, Jeff Gordon and Kasey Kahne, also were involved. So were defending Sprint Cup champion Brad Keselowski, new teammate Joey Logano, Carl Edwards, Kyle Busch, Jamie McMurray, Martin Truex Jr., Aric Almirola and Regan Smith.

Kahne's car sustained significant damage.

The wreck caused several teams to pack up and leave Daytona, and ended the pack racing that NASCAR wanted to see to evaluate its redesigned cars.