The gates opened as usual at a Vancouver city Olympic celebration site Wednesday, the day after 19 people were injured when fans at a rock concert pushed through a barrier.

Ten people were treated on site and nine were taken to hospital after the surge of fans caused a barricade to collapse during a free concert by Canadian band Alexisonfire at David Lam Park on Tuesday night.

Two people sustained lower leg fractures, and another had an injured knee, the city said in a statement Wednesday. The other six who were taken to hospital were assessed, treated and released.

The city said that the production company, Live Nation, removed the entire 43-metre concert barricade and installed another in its place.

"We sincerely regret that individuals were injured at David Lam Park," city manager Penny Ballem said in a statement.

"The city is gratified that the response was quick and professional, and relieved that the injuries were not more serious."

Ballem said in the statement that safety is the primary concern, and that the response was immediate.

"Finally, it is clear that the quick action of the band and Live Nation was important in optimizing the response to this incident. I want to thank the members of Alexisonfire and Live Nation," she said in the statement.

Ballem said the type of barrier used in the park has been in use for 20 years, and there's never been such an incident before.

"You know, the surge of the crowd definitely made a contribution to it but actually what happened, we don't know yet," she said in an interview with a local television station.

There were about 7,000 people crammed into the city celebration site at the time. The rest of the concert was cancelled along with a planned fireworks display.

Officials credit the band for quickly asking the crowd to back up, and for keeping the fans calm when the concert was cancelled and the site closed.

The site opened as scheduled at 11 a.m. Singer Corb Lund was to headline the lineup for Wednesday night.