West Ham United players were aware of Carlton Cole's clash with a fan at the end of their defeat to Wolves.
Police and stewards reportedly became involved following the Hammers' 3-1 defeat by Wolves at Upton Park on Tuesday night, while McCarthy saw his strike partner dragged away by his team-mates.
"I thought Coley knew the guy at first as they were speaking normally," said the South African.
"Eventually I saw some other players go back out and drag him inside.
"Maybe what went on today got to him and he reacted the wrong way."