Concerns over Vauxhall Zafira cars bursting into flames have deepened after a fire brigade released "shocking" figures which suggest the problem is becoming more common.
London Fire Brigade (LFB) told the Press Association that it has attended 71 such fires - not including arson attacks - since 2013, compared to just 38 in the previous four years.
Vauxhall is writing to 220,000 Zafira B owners to ask them to arrange for their car's heating and ventilation system to be inspected by a local dealer.
The manufacturer said the root cause of the fires is improper repair of the heater fan resistor's thermal fuse, which protects the system.
Sue Freemantle, 37, who is leading an online campaign for concerned motorists across the UK, expressed her alarm at the LFB figures.
Her campaign has received reports of more than 200 Zafira fires in total, and she believes Vauxhall is withholding important information from owners.
Mrs Freemantle, of Ivybridge, Devon, launched the campaign after her own Zafira caught fire in September.
She managed to escape with three of her children moments before the vehicle burst into flames.
LFB's director of operations, Dave Brown, said: "If you smell smoke or burning coming from your car while you're driving it, you should pull over as soon as you can in a safe place, get everyone out of the vehicle and always stay a safe distance away.
"Then call the fire brigade and never go back to the vehicle while you're waiting. If you are concerned that your vehicle is affected by the recall then contact your manufacturer immediately."
The brigade's insight and analytics team - which compiled the figures on Zafira call-outs - identify trends in a bid to protect the public by influencing strategy in relation to fires.