Cristiano Ronaldo could be questioned by police for careless driving

A dozen CCTV cameras will provide police with a second by second film of Cristiano Ronaldo's Ferrari horror smash.

It emerged yesterday officers may quiz the 23-year-old over allegations of careless driving.

Such a large number of cameras were installed in the 300 yard tunnel because of the terror threat to Manchester Airport and its runway directly above the tunnel.

Accident investigators are expected to examine the footage in minute detail to determine exactly why the Manchester United ace crashed his £200,000 supercar.

Officers are also probing claims the Portuguese star moved down a gear in his new Ferrari 599 as he roared into the tunnel on Thursday morning.

And they have been examining large skid marks still visible on the road to see if the star was driving within the 50mph limit.

Jody Lomax, who drove into the tunnel behind Ronaldo, said: "I was going into the tunnel and there was a Ferrari in front of me. It dropped a gear - it was an amazing sound. I put my window down to listen to the exhaust. It sounded superb.

"The Ferrari went straight into the wall. His front left-hand wheel came off, then Ronaldo got out - it was a shock. I was absolutely stunned."

Meanwhile, the £110,000-a-week player told his family the crash was not his fault, and said he catapulted the 205mph motor between the tunnel walls after skidding on oil. A family friend in Portugal said: "He said the crash was caused by moisture and oil on the road."

Ronaldo's mother Dolores, 55, is said to be deeply shocked by the accident. But he is thought to have assured her it was "nothing more than a scare, despite the state the car was in". United boss Sir Alex Ferguson bristled when the subject of the star's crash was brought up at a press conference ahead of the club's clash with Chelsea tomorrow. He refused to comment on the accident itself, saying only: "He's fit for Sunday's game."

The high-security tunnel is popular with boy racers and drivers have been known to use it for revving powerful engines to make the huge noise reverberate against the walls.

Films of drivers dropping a gear to maximise noise in the tunnel have been posted on video website Youtube.

One film, viewed more than 195,000 times, shows a Ferrari 360 Modena F1 zoom into the Manchester tunnel as the driver drops down a cog, making the powerful engine roar.

Ronaldo, recently named best footballer of the year in a poll of 32,000 fans across the world, is also expected to be officially named FIFA World Player of the Year in three days time at Zurich.

He was driving to training in the left-hand drive Ferrari, which he shipped to the UK from Portugal just this week. United colleague Edwin Van der Sar, 38, was driving behind him when he smashed the car and took him to train at United's Carrington complex after he miraculously emerged from the write-off unhurt.

Keeper Van der Sar is likely to be questioned by police as a witness to the crash.

Ronaldo yesterday drove himself to training in his £150,000 Bentley Continental GT convertible, another car from his £2 million personal fleet.

And showing what he thought of prying lenses, he was caught on camera cheekily sticking his tongue out.

A Greater Manchester Police source confirmed last night that it could take several weeks to finish the investigation into the cause of the crash because of the massive damage suffered by Ronaldo's Ferrari.