Security is tight in Bahrain as the Gulf state's Formula One Grand Prix has gotten underway, with reports indicating that anti-government protests overnight have resulted in fresh clashes.
Police fired tear gas and stun grenades at protesters, who responded by throwing rocks and fire bombs while chanting slogans against the kingdom's monarchy, AFP news agency reported.
Protests were reported to have been held in the villages of Malkiya, Karzakan, Sadad and Damistan.
Witnesses said the Sakhir circuit, where Sunday's race is taking place, was under complete lockdown, though protesters were briefly able to block some roads leading to the track by setting tyres and garbage on fire.
Black smoke from burning tyres hung in the air over Budaiya on Sunday morning. The village, located outside the capital, Manama, was the scene of mass protests on Friday.
"The atmosphere [around the Grand Prix] is tense," reported Al Jazeera's special correspondent, who we cannot name for security reasons, from Manama.
Kalil al-Marzooq, a spokesman for al-Wefaq, told Al Jazeera that Bahrainis felt the race was "not a big question".
"We have political problems. Especially the opposition itself ... [is] neutral about this event. We have people being killed. We have demands to return the power to the people rather than concentrating it on to the hands of the rulers," he said.
In Manama, police prevented planned protests at a central market, residents and witnesses said.
King Hamad bin Isa al-Khalifa, who was at the race, said on Sunday that he wanted "to make clear my personal commitment to reform and reconciliation in our great country. The door is always open for sincere dialogue amongst all our people".
Dozens of armoured vehicles and security forces in riot gear have been deployed along the road to the Bahrain International Circuit and around Manama.
Activists said barbed wire has been installed near some parts of the main highway.
Protesters have also been calling for the release of detained Abdul Hadi al-Khawaja, who is on the 74th day of a hunger strike.
Khawaja's deteriorating health has raised fears that he may die in custody, but Bahrain's interior ministry said on Sunday that he was in "good health" and would meet Denmark's ambassador later in the day. Khawaja is a dual citizen of Bahrain and Denmark.
The latest protests come a day after al-Wefaq, the country's main opposition bloc, said that a man had been found dead after clashes with riot police in the village of Shakhoura.
Al-Wefaq named the dead demonstrator on Saturday as Salah Abbas Habib, 37, and said his body was found on the roof of a building.
It said Habib was part of a group who were beaten by police during clashes late on Friday night.
Mohammed Eissa, Habib’s brother in law, told the Reuters news agency that police had not allowed the family to see the body when they went to the compound where it was found.
"We wanted to see it before it was taken so we can identify the body, but we were told to go the morgue and identify it there," Eissa said.
Al Jazeera's correspondent said that the body was "under police guard in a heavily secured hospital".
In a statement on the microblogging website Twitter, the interior ministry confirmed the death and said authorities have launched an investigation into the incident.
Wefaq's Marzooq said the government was tightly controlling information about Habib's death.
"All elements of the state are used against the people for repression," he said.
Habib's death came as the royal family pledged once again that the F1 event wold go ahead despite the ongoing protests by the country's mainly Shia population demanding greater rights.
Bahraini police fired teargas to break up a protest in an area outside Manama on Saturday and protesters responded with petrol bombs.
A witness told Reuters he saw up to 150 protesters, who had taken part in a march of several thousand people earlier for democratic reforms and against the staging of the Formula One race, and around 50 riot police in jeeps.
"Our initial demands were to elect a new government but after the disgusting abuse we received, all the people are
asking for is for the regime to fall," said protester Ahmed Madani during a march of 7,000 people on Saturday.
In another demonstration west of Manama earlier on Saturday, protesters carried banners depicting Formula One race drivers as riot police beat up protesters, activists said.
Violence has escalated in the run-up to the Grand Prix, which has come under huge criticism from country’s mainly Shia protesters, while the government wants the race to run as per schedule to send out a signal to the world of a return of normalcy.
"The government is using the Formula One race to serve their PR campaign," rights activist Nabeel Rajab said. "It's not turning out the way they wanted."
The protesters have blamed the Sunni ruling elite for shutting them out of opportunities, jobs and housing.
They have made it clear they will use the international attention the motor race has focused on Bahrain to air their grievances.
The rulers have depicted the race - expected to draw a worldwide TV audience of about 100 million in 187 countries - as an event that will put the divided society on the path of reconciliation.
The race itself has drawn more than 100,000 visitors and generated more than $500 million in spending. It has been a symbol of pride for the ruling family since the crown prince, Sheikh Salman bin Hamad Al Khalifa, brought the sport to the region in 2004.