Minor clashes ahead of Bahrain Grand Prix Security has been tightened for this weekend's Bahrain Grand Prix after pro-democracy protesters promised to mark the occasion with "three days of rage." On Friday, police stepped up patrols on the main highway leading to the Formula 1 circuit in the centre of the island. Authorities said they are determined that this year's race will go ahead following last year's cancellation when Arab Spring protests erupted in the Gulf state. On the eve of Friday's practice race, demonstrations flared in villages surrounding the capital Manama. Police fired tear gas and stun grenades to disperse the crowd. With its human rights record in the spotlight, Bahrain has been accused of using the race to rebuild its international reputation. Campaigners said the race is just part of a propaganda campaign. Hundreds of sports journalists have descended on the island while many international news reporters have had their entry visas for this weekend denied. It is not known how many fans will attend this year's race which costs 30 million euros to stage. More about: Bahrain, Formula 1, Grand Prix, Protest