A man started a fire at a Michigan petrol station by putting a lighter to what he said was a spider near his car's fuel cap, in the second US case this week where motorist arachnophobia has caused mayhem.

In the latest incident WJBK-TV said the man escaped injury and his vehicle suffered little damage, but the petrol pump was destroyed. A clerk shut off the pump from inside the station in Center Line, a suburb of Detroit, Michigan, and called the fire brigade.

The motorist can be heard on the surveillance video asking: "Is that a spider in there?" The video - sure to be a hit on the web - then shows flames erupting along the car's side, the pump and the pavement.

The man darts to safety and later uses a fire extinguisher to put out the flames. A spider is not seen.

The clerk says the man apologised the next day.

Earlier this week, terrified Angela Kipp jumped from her moving car after discovering a spider on her shoulder, leading to a crash that injured her nine-year-old son.

She was backing out of her driveway in Syracuse, northern Indiana, when she saw the spider and leapt out while the car was still in reverse gear.

Her son, who was in the back, climbed into the driver's seat and tried to step on the brake, but instead hit the accelerator pedal, sending the vehicle into a school bus.

He was taken to hospital with minor head injuries. No children were on the bus and the driver was not injured.