Hundreds of pro-democracy protesters have rallied in Bahrain's capital Manama against the scheduled controversial Formula 1 Grand Prix, which is scheduled for next weekend.

Demonstrators chanted "Your race is a crime", "Down with Hamad" (a reference to the king) and "The people want the fall of the regime", echoing the Arab revolutions' favourite slogan.

Clashes erupted when anti-riot police fired tear-gas to disperse the crowd and some demonstrators responded with Molotov cocktails. The interior ministry reported that one policeman was injured during the violence.

The rally came after Bahraini authorities launched a crackdown on opposition activists with local sources reporting increased house raids and arbitrarily detention of protesters.

Groups of police officers disguised as civilians have carried out night-time and dawn raids in the villages around the motor racing circuit "to spread fear and force silence among citizens" and thus "minimise protests and any media coverage of the continuous violations" by the Bahraini authorities during the race, according to the Bahrain Centre for Human Rights (BCHR).

Last year, the Bahraini Grand Prix took place in April despite worldwide calls for a boycott, against the backdrop of violence on the streets of Manama which caused death and injury during the race weekend.

Former Formula One world champion Damon Hill has said that a race should not take place in Bahrain over human rights concerns.

He called on FIA president Jean Todt to take an ethical stance on the controversial event. "I think Jean's approach is say nothing because otherwise you are being political," said Hill, who won the world title in 1996.

"I think that is a mistake because actually he is being political because he's being used, or the sport is perceived as being used, by its engagement in the economy and the reputation of the country."

Bahrain was the first Middle East country to host a grand prix in 2004, but sponsors are saving money for less politically sensitive races such as Abu Dhabi, Reuters reported.

"Abu Dhabi has taken a lot away from Bahrain. Notwithstanding the trouble in Bahrain, the Abu Dhabi race is more interesting for sponsors," said Jim Wright, a sponsorship consultant who worked in the sport for 18 years.

Thomson Reuters said it would not have any branding at the race in Bahrain. It did not elaborate any further. Another two brands, Johnnie Walker whisky and Vodafone, will skip the upcoming Grand Prix. Bahrain pays an estimated $40 million annually to be part of the 19-race calendar, making it a valuable fixture for the sport.

Formula One boss Bernie Ecclestone, who last year said he was not concerned over Bahrain once again hosting a grand prix despite the ongoing crackdown on pro-democracy protests, said last week he has not had "any negative reports from anybody there."