Thousands of protesters took to the streets across Bahrain on Friday to demand political reforms, as the country's Formula One weekend got underway with drivers hitting the circuit for their practice runs.

Some of the protesters flooded part of a major highway that links the capital, Manama, with Bahrain's F1 track.

"We demand democracy," and "down, down Hamad," the protesters chanted, in a reference to the country's king, Hamad bin Isa Al Khalifa.

Security forces decked out in riot gear moved in with tear gas and stun grenades to stop a group of protesters that tried to move towards a traffic roundabout, which had been a rallying point during an uprising that led to the cancelation of last year's Bahrain Grand Prix. The Reuters news agency reported that police moved on the crowd after masked youths had pelted them with petrol bombs. There were no immediate reports of casualties.

Bahrain's leadership stands firm

However, following the practice session, which took place behind a cordon of security forces, Crown Prince Salman bin Hammad rejected the protesters' demands that the F1 event be canceled.

"For those 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," the prince said.

Security forces were out in high numbers along major routes leading to the racetrack to ensure that the F1 event could go ahead despite the protests, which were organized by some of the country's Shiite political groups.

Sheikh Isa Qassim, a leading opposition Shiite clergyman used his Friday sermon to denounce the government's decision to go ahead with the event despite the objections of much of the country's population.

"Whether the (F1) race is canceled or not, whether someone supports it or not, the people's choice is clear," he said at a mosque in a village north of the capital.

"And nothing will deter the people," he added.

pfd/mz (dpa, Reuters, AP)