SECURITY at the Shanghai International Circuit has been beefed up after a Formula One 'fan' was arrested following a death-defying dash across the track during practice today.

The local man, in possession of a grandstand ticket that overlooks the pits, initially scaled 10-foot high catch fencing that runs along the main straight.

With cars flashing by at speeds of over 200mph, the spectator picked his moment to dart over the starting grid as a Sauber had just passed by and with a Force India approaching in the background.

The man then jumped through a gap in the pit wall and ran across the pit lane before entering the Ferrari garage.

It was there he was finally grabbed by security staff and handed on to police for arrest, but not before apparently stating he wanted to drive a car.

The incident was similar to the one at the 2003 British Grand Prix when former priest Neil Horan ran down the Hangar Straight wearing a kilt and sporting a religious message on a placard around his neck as cars took evasive action.

Horan later pleaded guilty to a charge of aggravated trespass and was sentenced to two months' imprisonment.

On this occasion, red-faced Chinese officials have decided to double their security detail around the entire circuit for the weekend's events that include qualifying on Saturday and in Sunday's race.

Following a meeting with FIA race director Charlie Whiting, clerk of the course Zhang Tao has ordered the heightened security measures to ensure there is no repeat of the incident.

As for the real action on the track, it was reigning champion Lewis Hamilton who led the way at the end of both of the 90-minute sessions.

Following the shock victory in Malaysia last time out for Ferrari and Sebastian Vettel, Mercedes and Hamilton appear poised to hit back.

Hamilton, a three-times winner of this race, including last season, finished 0.541secs quicker than team-mate Nico Rosberg at the end of FP1 when Pirelli's medium-compound tyres were used.

Switching to the faster soft tyre for FP2, Hamilton again comfortably had the edge by 0.443secs over Ferrari's Kimi Raikkonen.

A satisfied Hamilton, who missed almost an hour of FP2 in Malaysia a fortnight ago with a power unit issue that compromised the remainder of his weekend, said: "Today was definitely an improvement on Friday then. It was good to get both sessions in, which puts me in a stronger position, and the team has done an amazing job to find improvements in the car.

"Balance-wise it's way better than the last race. Generally it was feeling really good. I don't know how long I went on each compound (of Pirelli tyre), but it felt good on the long and short runs.

"The prime (medium compound) perhaps didn't feel as good as the option (soft compound), but I'll have to go and analyse the data to see where we are compared to the others."

Despite the gap to Raikkonen and Vettel, who was fourth quickest and 1.120secs adrift of Hamilton, the Briton added: "It was quite close between us and Ferrari.

"They look just as fast as they were last time out and Nico was quick as well, so we definitely have a race on."

However, a confident Hamilton added: "I feel like I've some improvements to make and I think we've got the pace to stay ahead."

Daniel Ricciardo was third quickest, 1.093secs adrift in what was a stark improvement for Red Bull compared to their form over the first two races.

However, team-mate Daniil Kvyat's session ended with 20 minutes remaining due to a left-rear brake fire.

McLaren's Jenson Button was 10th, two seconds down as he and the team continue to show signs of improvement, with team-mate Fernando Alonso 12th and a further half a second off the pace.

Button said: "We look reasonably good out there. But that can perhaps be explained by the fact we seem to have been able to extract the maximum out of our car, whereas perhaps some of the other teams haven't.

"Still, the car feels nice to drive, although there's still plenty of room for improvement, but I'm looking forward to the rest of the weekend nonetheless."

Felipe Massa brought out the only red flag of the day due to a rear-wing problem at high speed that saw slide off track and clip a tyre wall, resulting in the Brazilian missing the last 52 minutes of FP2.

Manor duo Roberto Merhi and Will Stevens brought up the rear, the latter encountering electrical issues that restricted him to eight laps.

Despite that, after missing qualifying and the race in both Australia and Malaysia due to other difficulties, Stevens is confident he will be on track on Sunday.