An elderly woman has told police she had no idea they were chasing her for 25 minutes in Rotorua yesterday, or that her car only came to a stop after she drove over road spikes.

Even the sounds of the police car's sirens and flashing lights allegedly failed to stop the driver.

Several people had called police complaining about an erratic driver on State Highway 5 around midday yesterday, Rotorua area commander Inspector Bruce Horne told the Daily Post.

Police located the vehicle a few minutes later and a 25 minute chase ensued.

They used sirens and flashed the car's lights to signal to the driver to stop, but even this failed to work, Horne said.

"Although the vehicle was travelling at a speed within the prescribed limit at all times, the manner in which the vehicle was being driven was of concern to police and created concern for the safety of both the driver and other road users.''

The driver appeared to be completely oblivious to the police presence, he said.

A check point set up by police officers ahead of the vehicle also failed to get the driver's attention, Horne said.

The woman would have probably kept on driving if it wasn't for road spikes police laid in her path.

But when her car finally came to a stop, the elderly driver had no idea that her tyres had deflated because of the road spikes.

She has not been charged but police were talking to her family about the status of her driver's license, Horne said.