Firefighters were called to the incident at 3.07am after police discovered the playground at the centre of the Bridge Mall alight.

A spokesman from Ballarat City fire brigade said it was lucky the fire had only just been lit so firefighters were able to extinguish the flames before it caused serious damage.

This comes after three council-owned rubbish bins in the Bridge Mall were totally destroyed, while another two were seriously damaged after a series of deliberately lit fires early on Sunday morning. 

Both incidents are currently under police investigation.

A tall man, believed to be in his 20s was seen leaving the mall near the time of the blazes on Sunday with police interested in speaking with him. They do not know if he is connected to the fires. 

Anyone with information is asked to call Crime Stoppers on 1800 333 000 or Ballarat Police on 5336 6000.