Residents in Staffa Crescent, Blackburn were startled awake after a line of cars parked on the street outside their homes caught fire at around 2am.
Five cars were completely destroyed in the suspected arson attack in the Shadsworth area.
Three fire engines from Blackburn and Hyndburn were mobilised, and firefighters had to equip themselves with breathing apparatus to shield them from thick smoke.
The fire service said the cause is believed to be suspicious.
Crew manager Ally O’Donell, from Blackburn Fire Station, said: "We were called to Staffa Crescent in Shadsworth at around 2am after reports of several cars on fire.
"It looks like the fire started after one car was ignited, and then it quickly spread to another four cars.
"Running fuel - which appears to be petrol, has leaked down the street spreading the fire to the other cars.
"It appears to have been a deliberate act and we have reported our concerns to the police.
"An investigation has now been launched to establish the exact cause of the fire."
Megan-Louise Day is one of the unfortunate Staffa Crescent residents who woke up to find her car engulfed in flames.
Her Peugeot 208 (pictured) had been completely consumed by the fire.
She said: "Someone poured petrol over the car behind mine, my dad woke me up because he heard a tyre pop.
"It was like the whole street was on fire. It could have easily spread to our houses."
Lancashire Police said: "It has been reported to us and we are investigating alongside the Fire Service."