Nico Rosberg has emerged as the man to beat in qualifying for the Bahrain Grand Prix on a morning when a full complement of cars again took to the track.
It comes as armoured vehicles were deployed onto the streets of the Bahraini capital Manama following another night of clashes between police and protestors.
Pro-democracy campaigners are set to intensify demonstrations in Bahrain ahead of tomorrow's controversial grand prix.
Race organisers and the kingdom's rulers insist it is right the race should go ahead.
Force India yesterday pulled Nico Hulkenberg and Paul Di Resta from FP2 for safety reasons after four members of the team were caught up in a petrol-bomb incident on Wednesday.
Both men returned to action at the Bahrain International Circuit today in the final hour-long practice session, but were well off the pace set by Rosberg.
After claiming his maiden pole and race win in China last weekend the confident 26-year-old has now been quickest in the final two practice outings for Mercedes.
However, his time today of one minute 33.254secs was almost four tenths of a second off his best yesterday, but still 0.147secs ahead of reigning world champion Sebastian Vettel.
With Red Bull looking stronger in Bahrain than they have in the first three races, Mark Webber was third quickest, 0.409secs adrift, with Lewis Hamilton fourth in his McLaren 0.528secs down.
Mercedes’ Michael Schumacher was hot on the heels of Hamilton but, like the Briton, also half a second down, with Jenson Button down in sixth.
Lotus duo Kimi Raikkonen and Romain Grosjean were seventh and ninth, sandwiching the Toro Rosso of Daniel Ricciardo, with Ferrari’s Fernando Alonso 10th but struggling 1.641secs behind Rosberg.
As for Di Resta and Hulkenberg, they were 15th and 19th, two and 2.5secs adrift respectively, with Ferrari’s Felipe Massa a lowly 16th as the Brazilian continues to languish.
Off the track, pro-democracy campaigners are set to intensify demonstrations in the kingdom today following a day of violent clashes with riot police in the Gulf state.
Around 50,000 anti-government protesters gathered in the capital yesterday as Formula One stars took to the track of The Bahrain International Circuit (BIC) just 25 miles away.
Petrol bombs were hurled at security officials and anti-grand prix graffiti was daubed on walls, before the throngs of protesters were dispersed with rounds of tear gas and pepper spray.
Activists billed yesterday as the first of “three days of rage” against Bahrain’s rulers with thousands more expected on the streets today demanding democracy and the cancellation of the controversial motorsport event.
However, defiant F1 organisers bosses are refusing to scrap the three-day event despite months of political unrest and the regime’s crackdown on demonstrators.
Bahrain’s Crown Prince Salman al-Khalifa said that cancelling the race would “empower extremists”.
“For those of us trying to navigate a way out of this political problem, having the race allows us to build bridges across communities, to get people working together,” he added.
“It allows us to celebrate our nation. It is an idea that is positive, not one that is divisive.”
F1 supremo Bernie Ecclestone had earlier insisted it was down to the Bahrainis to cancel their grand prix.
Meanwhile, the sport came under attack from cyber anarchists with internet hacking organisation Anonymous announcing they would turn the formula1.com website into “a smoking crater in cyberspace”.
The denial-of-service attack, under the title of ’Operation Bahrain’ after watching what they perceive as “the incredible human rights abuses of the Bahrain regime”, was unleashed shortly after Crown Prince Salman’s comments.
Violence has been intensifying in Bahrain ahead of the grand prix.
A car carrying four personnel from racing team Force India was caught up in a petrol bomb incident on Wednesday night as it made its way back from the BIC.
None of the four were injured, but two team members – one of whom was involved in the incident – have since flow home due to fears over safety.
Amnesty International said human rights violations are continuing in the Gulf kingdom despite government promises that the country is on the road to reform.
In a recent report, the campaign group said security forces were still using excessive and unnecessary force against anti-government protesters.
The charity also said it was receiving ongoing reports of the torture and ill-treatment of demonstrators, who have been involved in ongoing clashes with police.
The 2011 race was cancelled as international criticism grew over the bloodshed.