Two teenagers have been arrested after a woman and a boy suffered burns as flares were ignited at an A-League match in Melbourne on Friday.

Police say a number of flares were let off during the second half of Melbourne Victory’s clash with Brisbane Roar at Etihad stadium, leaving a woman, in her 20s, and a boy, 12, with burns.

Two teenage boys have been arrested and are assisting police with their inquiries.

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North West Metro Commander Rick Nugent said letting off flares was dangerous and illegal.

“Flares are extremely dangerous. They can burn at more than 1000 degrees Celsius and are not designed to be released in highly populated areas,” he said.

“The increased criminality we are seeing at the soccer this season is completely unacceptable.

“It is disappointing to see this increase in this behaviour as the clubs, the FFA (Football Federation Australia), the league, Victoria Police have worked hard and tirelessly to improving community safety at A-league games.

“Last year we had quite a successful season in terms of significantly reduced anti-social behaviour, violence and criminality at games.

“This year, I suspect part of it is that we have young people joining the active supporter areas that are being led astray by some older and more experienced people and are now embarking upon this sort of conduct.”

Since the first match on October 10 this season, 38 flares have been let off and about 200 chairs broken, he said.

Commander Nugent said most of the 22,000 people attending Friday night’s match were well behaved, but a certain group of individuals had other motives.

So far this season, about 30 people have been arrested at Victorian A-League matches.