POLICE are hunting rowdy footy fans who injured a nine-year-old boy at last night’s A-league clash.

A Victoria police spokeswoman confirmed the child had received medical treatment after being struck by a plastic bottle during the match between Melbourne Victory and Melbourne City at Etihad.

The incident came as some other supporters lit flares, and behaved badly.

MATCH REPORT: Melbourne Victory v Melbourne City

“Police will review the match and crowd behaviour overnight and will have more to say,” she said.

It was unclear last night whether the child was taken to hospital to have the injury treated.

media_camera Crowds cheer through a flare at Etihad Stadium. Picture: Rob Leeson.

media_camera A sniffer dog searches fans at Etihad. Picture:Rob Leeson.

Police and stadium security evicted 10 people at the derby — four for discharging a missile, three for unruly behaviour, one for pitch invasion and two for possession of flares.

Four flares were ripped inside the stadium, including one in the Melbourne City active area about the 60-minute mark in the second half, while 25 flares were released outside the stadium.

Fans reportedly let off flares in Southern Cross Station before the match.

A large increase in the use of flares at A-League matches in Melbourne has forced police to send in the hounds this season.

Tonight’s violence comes after the Herald Sun revealed there were 145 flares thrown at matches in Melbourne last season compared with 12 the previous year.

anthony.galloway@news.com.au