A man has died after an alleged police pursuit at Kambah in Canberra's south.

The man was in one of three vehicles involved in the accident on the corner of Drakeford Drive and Marconi Crescent in Tuggeranong about 6:00pm on Friday.

At least two people had to be cut from the wreckage and taken to hospital with serious injuries, after their car was wrapped around a light pole.

Another car was sitting nearby on its roof.

All north-bound traffic on Drakeford Drive remained blocked by police well into the night.

A major investigation has begun into the alleged high-speed police pursuit.

Rebekah Hunt witnessed the crash and said one of the cars was being chased by police.

"I was driving through and they were getting chased by a police car," she said.

"I saw them go through the first red light and I thought 'Oh my God, this person's crazy', and a police officer was then chasing him.

The wreckage from three cars involved in the fatal accident was left along Drakeford Drive at Kambah. ( ABC News: Damian Porombka )

"The lights turn green to go and all of a sudden there's just smoke everywhere along the intersection.

"I was just mortified, it was awful, when I finally turned right there was just debris everywhere."

Ms Hunt said the car being pursued by police was "going at least 200 kilometres an hour".

"My friend who was next to me was having a panic attack, so I had to take her immediately home," she said.

"She was shaking and she said 'I wish I'd never seen that, my life would be better if I didn't see that'.

"She was almost in tears ... she doesn't want to be on these roads after what she's witnessed."