Uruguay coach Marcelo Bielsa on Friday defended his players involved in a clash with Colombian fans after Wednesday's Copa America semifinal, saying "anyone would have reacted like that" to protect their families.

After Colombia sealed a 1-0 victory in Charlotte, North Carolina, Uruguay players climbed into the stands, exchanging blows with opposition fans.

Uruguay says players' family members had been assaulted by Colombians in the stands. Bielsa was outraged after South American soccer governing body CONMEBOL, who organised the Copa, opened an investigation into Uruguay and criticised it for failing to protect the families.

"You know whose responsibility it is to protect the fans in the stands. You have to ask me whether the players have received an apology from those responsible for safeguarding security," the former Leeds United manager told reporters on Friday. He did not fear possible sanction, he added.

"The players reacted as any human being would have done if they saw that there was no escape or prevention and they were attacking their wife, mother, a baby," said Bielsa, who is Argentine.

"What should they do?... Nobody wants to see a violent reaction, but you have to look at what a reaction is in response to."

The Uruguayan football association (AUF) also said there was a lack of security in the stands which led to "an unjustified but humanly understandable reaction" by the players.

"This event took place in a context in which the proportion of Uruguayan fans was very small. Most of them were families, and there were insufficient security measures in place," the AUF said in a statement.

"Given these facts, the players' behaviour was inevitable and natural," it said, adding though that it "strongly condemned" their aggression.

CONMEBOL did not respond to a request for comment on the accusations about a lack of security. It is investigating 11 Uruguayan players.

Uruguayan sports minister Sebastian Bauza said some players will miss at least the next two World Cup qualifiers in September.

"We have players who, for sure, will be suspended for the two qualifiers we have left this year (against Paraguay in Montevideo and away to Venezuela)," Bauza told Uruguay's Canal 10.

"Hopefully, it will be as few games as possible and as few players as possible."

Uruguay will play again at Charlotte's Bank of America Stadium for the Copa America third place against Canada on Saturday.