Bahrain protesters clash with police over anti-Formula One rage

Groups protesting Bahrain's Formula One race have put up makeshift roadblocks and barricades of burning tires during clashes with security forces in the violence-wracked Gulf nation.

The demonstrations on Thursday were mostly isolated to anti-government hotbed areas, however, and unlikely to disrupt preparations for Sunday's race, which is the premier international event in the kingdom.

Anti-government groups have stepped up protests against the race in attempts to embarrass authorities. Rights group, including Amnesty International, have criticized Bahrain's arrests and other security crackdowns.

The latest clashes were mostly in Shiite districts that are often scenes of unrest. Graffiti on walls said: "No F1. Don't race on our blood."

Bahrain has faced more than two years of violence between the Sunni-led government and majority Shiites seeking a greater political voice.