Detectives are investigating after a fire broke out in Birkdale Village last night.
Emergency services were called to the rear of a massage parlour on Liverpool Road on Monday evening after residents were overwhelmed by the smell of smoke.
Fire crews attended and are understood to have extinguished a small fire on the property
A criminal investigation is now underway.
Detectives from Merseyside Police and a specialist arson investigation unit from Merseyside Fire and Rescue have sealed off the building and are conducting an investigation into the cause of the fire.
Anyone with any information should call 101.