Felipe Massa has apologised after one of his team-mates at a 500-mile go-kart race was involved in an on-track brawl on Saturday.
The Brazilian former F1 driver was participating in an event in Sao Paulo, but it ended in a controversial fashion when two drivers, Rodrigo Dantas and Tuka Rocha, clashed on the track 18 laps from the end of the race.
Rocha, who was second behind Massa at the time the incident occurred, was driving for a team led by Brazilian Stock Car driver Thiago Camilo, while Dantas was on Massa's side.
Dantas attempted to block Rocha's way past Massa, with the two colliding several times throughout the event, before Rocha pushed Dantas into the tyre barrier.
The pair jumped from their karts to confront each other, before Dantas pulled Rocha to the ground and punched through the visor of his helmet repeatedly - scroll down to see the incident.
Security guards were then called to break up the altercation, with both teams disqualified, meaning Massa was denied a victory in the process.
Skip to 0:20 in the video below to watch the events unfold.
The 36-year-old was upset with his team-mate following his involvement in the brawl.
"From what I saw, the whole team should be disqualified," Massa said. "But that did not happen, and what happened next was a war inside the track.
"For me, this is very sad and sadder still to see my team within that. It was not my decision -- I was driving my kart [in the lead] -- but I apologise to everyone for what happened, because I have never seen anything like it in my career.
"The competition is inside the track, but never in this way."
Massa has only just recently retired from Formula One, having called it a day for one final time at the end of the 2017 season after a 16-year career.
He has recently been appointed FIA's International Karting Commission's President following his retirement from F1.