Police are investigating an incident where significant damage was caused to a number of Devonport CBD businesses.

Police were called to the corner of Best and Rooke streets about 5am this morning, after reports of flooding on several levels of a commercial building.

Detectives believe a person has entered the building and caused the damage.

Several businesses on the ground floor were impacted, and TasWater was called to assist.

Anyone with information or who witnessed suspicious activity in the area early this morning should contact Western CIB on 131 444 or Crime Stoppers anonymously via crimestopperstas.com.au