NASCAR has fined Brad Keselowski and Tony Stewart for their post-race conduct at Charlotte Motor Speedway.

Keselowski was fined $50,000 and Stewart was fined $25,000. NASCAR said Tuesday it was trying to maintain "a safe environment following the race."

Matt Kenseth and Denny Hamlin were not penalized for their roles in the post-race skirmishes after Saturday night's race.

Keselowski and Hamlin tangled on the track after the checkered flag, and Keselowski hit Kenseth on pit road. He then inadvertently ran into the back of Stewart, who put his car in reverse and hit Keselowski's car in retaliation.

Hamlin followed Keselowski in his car to the garage and had to be restrained from confronting him. Kenseth jumped Keselowski from behind, but crew members broke up the fracas.