Bahrain march hints at rising anger over upcoming Formula One race

A Bahraini anti-government protester prepares to throw a petrol bomb at riot police during clashes following a rally protesting against the upcoming Formula One race in Sanabis, Bahrain, Tuesday, April 9, 2013. The Bahrain Grand Prix is to be held April 21. Bahrain says four suspects have been arrested after homemade firebombs were hurled at the foreign ministry in a possible escalation of anti-government protests. (AP Photo/Hasan Jamali) (The Associated Press)

Thousands of anti-government demonstrators in Bahrain have joined a march that included breakaway protests against the scheduled Formula One race later this month.

The anger against the F1 event appears lower than last year but rights groups say security forces have expanded arrests and crackdowns near the track. Opponents of the race have vowed wider protests in the coming week.

The race is Bahrain's premier international event. It was cancelled in 2011 as the Arab Spring uprising engulfed the Gulf kingdom. In 2012 it went ahead despite huge demonstrations.

Friday's protest, authorized by the government, included a line of marchers more than 2-kilometers (1.2-miles) long.

Bahrain's majority Shiites have pressed for a greater political voice on the Sunni-ruled island, which is home to the U.S. Navy's 5th Fleet.