MANAMA, Bahrain (AP) — Organizers of Bahrain’s Grand Prix said Thursday that sporadic protests against the race and violent unrest across the Gulf nation do not pose a threat to the premier international event in the kingdom.

Anti-government groups have stepped up protests against the race in attempts to embarrass authorities, but the demonstrations have been mostly isolated to areas that are hotbeds of opposition to the ruling royal family. Rights groups also are using the race to criticize Bahrain’s arrests and other security crackdowns.

Zayed Alzayani, the chairman of the Bahrain International Circuit, said security measures in place this week at the circuit were no different than in past races. Police vehicles dotted the road leading to the circuit and there were several checkpoints before the track.

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“We don’t feel there is a direct threat to the track nor have we received any threats to the track,” Alzayani said. “But we take everything into account. For us, we want to produce an event that is memorable for those who attended.”

Alzayani insisted that Sunday’s race, which is biggest event in the Gulf nation and generates as much $220 million, is a unifying force in the country and that a majority of Bahrainis were backing it. He said ticket sales were up 20 percent over last year with 25,000 fans expected at the race.

“One of the distinctions of our race, when compared to other races around world, is you have total buy in from the nation,” he said. “The race has been endorsed by all members of society, including the opposition. If there are people who are against the race, that is fine. They are entitled to express their opinion within the confines of the law.”

Bahrain has faced more than two years of violence between the Sunni-led government and majority Shiites seeking a greater political voice. The latest clashes occurred mostly in Shiite districts of the country, which are often scenes of unrest. Graffiti on walls said: “No F1,” a reference to the Formula One event. “Don’t race on our blood.”

The race was postponed in 2011 after the Arab Spring-inspired uprising hit the country. The 2012 race was held, but was remembered more for massive protests before the event rather than Sebastian Vettel’s victory.

One man died last year near the scene of the demonstrations, but this year there has been less attention on the race from rights groups and the protests so far have been smaller and less violent.

Still, rights groups have used the race to highlight what they contend has been the slow pace of reform on the strategic island nation, home to the U.S. Navy’s 5th Fleet. They also complain of widespread arrests in the weeks preceding the race in villages surrounding the circuit.

There were clashes much of Thursday between stone-throwing protesters and riot police firing bird shot and tear gas, said Yousef al-Muhafedha, acting president of the Bahrain Human Rights Center. Thirteen people were detained and three were injured, he said.

The Ministry of Interior said seven people have been detained, including one person for a “car explosion” in Bahrain’s new financial district. It provided no other details about the explosion. Four others were detained for stealing a car and burning it, and another for blocking a highway.

“Instead of responding to the uprising of February 2011, the last two years have seen continued killings, arbitrary arrests and alleged torture in Bahrain,” said Hassiba Hadj Sahraoui, deputy director of Amnesty International’s Middle East and North Africa Program. “The authorities are trying to use the Grand Prix as a platform to show progress, with claims that the human rights situation has improved, whilst stepping up repression in order to ensure nothing disturbs their public image.”

Several groups have called for the race to be canceled, including a group of British parliamentarians who sent a letter to Formula One chief Bernie Ecclestone.

Responding to several rights groups concerned about the race, Jean Todt, the president of F1A, the governing body of world motor sports that includes Formula 1, said in an email that it is “our firm belief that sports, and the F1 Grand Prix, can have a positive and healing effect in situations where conflict, social unrest and tensions are causing distress.”

At the Bahrain International Circuit, the only driver who talked extensively about the political situation was Red Bull’s Mark Webber who had raised concerns about holding the race last year. He said he had “softened” his stance this year after the 2012 race was held without incident.

“We proved in past the event as a whole can go off not too badly,” Webber said. “It’s awkward but we have shown we can have the event but there is still one eye on what is happening here. … We need to try to, as a sport we love, to do whatever we can for the fans and make sure the countries (where) we go, everything is as good as possible. We can’t control everything.”

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