A mystery woman driver stopped to wake sleeping residents when fire broke out in their block of flats.

Arsonists have been blamed for setting fire to a mattress in the ground-floor lobby of four-storey Parker Court in Foredown Road, Portslade, at 5.30pm yesterday.

The woman passing the burning building stopped to encourage people living there to get out as soon as possible.

Ground-floor residents Lyn Strong, 31, and her four-year-old son Louie were asleep before the woman intervened.

Mrs Strong said: "The woman woke me up and told us to get out as quickly as possible, saying there was a fire.

"I didn't really see the flames but I saw lots and lots of thick smoke. It was frightening.

"It was lucky she was passing by and stopped because there are no communal smoke alarms here. I wanted to say thank you but she'd already gone by the time I got the chance."

One woman was treated for the effects of smoke inhalation but no one was hurt.

Leading firefighter Keith Darlington, from Hove fire station, said: "This could have been very serious. Some residents managed to get out but others were contained inside their flats because the fire was blocking the stairwell.

"We managed to put the fire out quite quickly but there was a lot of ventilating to do."

The fire is being treated as suspicious and an investigation has begun.

Crews from Preston Circus station dealt with a car fire in Church Street, Brighton, which spread to the ground floor of a nearby shop at 5.50pm yesterday. No one was hurt.

Crews covering Brighton from Lewes fire station were called to a terraced house in Cheltenham Place, Brighton, at 5.15pm yesterday when a settee on the first floor was set alight.

When firefighters arrived, no one was in the building which suffered burnt floorboards and ceilings.

Sub Office Rob Martin said: "Luckily we managed to stop the fire going through the roof."

Crews were there for about an hour.