A Hamilton teen has been arrested after a fire caused $20,000 worth of damage to an east end building Tuesday – one that happened while people were still inside, police say.

Police and fire officials were called to 209 Ottawa Street North just after 2:25 p.m. after a person was heard yelling for help inside the smoking building.

The fire was doused and there were no reports of injuries. Initial estimates on property damage are around $25,000.

Police investigated and have arrested a 16-year-old from Hamilton, who has been charged with arson endangering life.