Two teenage boys suffered upper body injuries as tables and chairs were thrown in a violent brawl outside a Brunswick East restaurant on Friday night.

Waiters locked themselves inside the restaurant as two groups clashed outside the Hanging Gardens Restaurant, hurling furniture across the footpath.

One staff member said he and his colleagues stayed inside during the fight, which lasted for between five and 10 minutes.

The group had left a nearby bar about 11.30pm, after celebrating an 18th birthday, Seven News reported.