SYDNEY -- Australian police arrested a man fitting the description of an outback gunman they fear killed a British tourist and tried to kidnap his female companion 10 days ago, Reuters reported on Tuesday.

Police detained the man on outstanding warrants in the inner Sydney suburb of Tempe after pulling over a pick-up truck which matched one used by the gunman in the outback ambush in the sprawling emptiness of the Norern Territory.

"If he turns out to be our guy then we will arrest him," said a police spokeswoman in Alice Springs in the Northern Territory, adding the man fitted the description of the gunman they sought.

British tourist Peter Falconio, feared shot dead by the gunman, has not been found since he and his companion Joanne Lees were attacked on the isolated Stuart Highway in the Northern Territory.

The gunman flagged down the British tourists, pretending there was something wrong with their Volkswagen van.

When Falconio and the gunman walked to the rear of the van, Lees heard a gunshot and was then dragged away, bound and gagged.

She managed to escape into the bush where she was hunted by the gunman and his dog. Lees evaded the gunman and finally flagged down a passing truck driver, pleading for help.

A massive police manhunt with aircraft and aboriginal trackers over the Northern Territory -- an area five times the size of Britain -- had failed to find the gunman or Falconio.

But on Tuesday morning Sydney police received a call from a member of the public who had seen a pick-up truck near Sydney Airport which matched the vehicle used by the gunman.

Police pulled over the dusty, yellow pick-up truck, with front bull bar and tarpaulin cover, and questioned the driver, arresting him on outstanding warrants in the state of New South Wales.

Police did not say what offences the man was arrested for.

"New South Wales police are speaking to a man located in Tempe this morning with a vehicle which fits the description by Northern Territory police," a police spokeswoman told Reuters.

Police photographed the pick-up truck in the street where it was stopped before towing it away for forensic examination, while the man was taken to Sydney police headquarters for questioning.

An eyewitness to the arrest told a sydney radio talk-back program the man did not resist arrest, but shouted "I am innocent" when taken away.

The eyewitness, identified as Steven, said the man had a dog in the back of his pick-up when police pulled him over.

"The police officer pulled him over and took him out of the car and put him in the back. He was wearing a green coat, long black hair. I saw a dog in the back when he was getting pulled over," he said.