A man is in critical condition after a fire tore through a block of flats in Paisley.

The 51-year-old was rushed to the town's Royal Alexandra Hospital following the blaze, which started in a ground floor flat on George Street shortly before 9pm on Monday.

Another man, whose age is unknown, and a six-year-old boy were also treated for smoke inhalation but have since been released from hospital.

All three were injured after smoke and flames spread from the ground floor flat, which was unoccupied at the time.

A number of other residents were evacuated from the block during the fire.

Police are treating the blaze as suspicious and are appealing for any witnesses to come forward.

Detective inspector David Wagstaff from Paisley CID said: "Officers, including a forensic team, are carrying out a search of the flat and also speaking to neighbours in an effort to trace the person responsible for the fire.

"Whilst there may have been no one in the flat that was targeted, this irresponsible and thoughtless act has resulted in a neighbour being seriously ill in hospital."

He added: "George Street is residential and it is entirely possible that people would have been in the street or driving by at the time of the incident.

"I would appeal to anyone who may have seen someone running from the flat or anyone acting suspiciously in the area between 8.45pm and 9pm to contact police."