MANAMA // Police used tear gas and sound bombs yesterday to disperse thousands of Bahraini opposition supporters blocking a motorway outside the capital.
It was the second day of protests marking the anniversary of the 2011 uprising, inspired by the Arab Spring.
Authorities said they had launched investigations into the two deaths from Thursday's protests.
A policeman died late that night after being hit by an object thrown by protesters, authorities said.
A 16-year-old protester died earlier in the day after being hit in the stomach with birdshot.
Dozens of people were also injured in Thursday's clashes between protesters and police in Shiite-majority villages from early morning into the night.
The chief of public security, Maj Gen Tariq Al Hassan, yesterday said the bomb-disposal unit had defused a 2-kilogram explosive device on the King Fahd Causeway linking Bahrain and Saudi Arabia.
Protests again started early yesterday as thousands of mourners chanted anti-government slogans at the 9am funeral of a 36-year-old woman in Abu Saiba village.
The opposition said Amina Sayed Mahdi suffered rheumatoid arthritis, which can cause breathing difficulties, and was affected by inhaling tear gas.
In the late afternoon, tens of thousands joined a march organised by the political opposition along the Budaiya motorway, which links several Shiite villages to Manama.
Some held signs that called for the end of "dictatorship" on the island.
"We're looking for democracy and we want to deliver a message to the government that we are doing something," said Hussein, 18-year-old protester on the edges of the march.
A small number of youths tried to breach military barriers surrounding the former Pearl Roundabout in mid-afternoon.
The anniversary of the February 14, 2011 uprising, when pro-democracy demonstrators convened at the central Pearl Roundabout, sparked a broad range of emotions across Bahrain.
Opposition supporters, many of whom are from the Shiite community, say they suffer systematic discrimination and marginalisation in Bahrain's politics and economy.
The mainstream political opposition has called for constitutional monarchy, while youth groups and many protesters demand more radical political change.
"We won't stop until the fall of the regime," said the protester Majid Abdulaziz, 38.
But in some quarters, February 14 was celebrated as the 11th anniversary of a referendum on political reform that granted more power to elected authorities, the National Charter.
Presented to the country by King Hamad, the measure was approved with 98.4 per cent of the vote in 2001.
The referendum's anniversary was marked with a fireworks display on Thursday evening as clashes continued in several Shiite-majority villages.
Divisions between pro-government and opposition camps were also on display this week when delegates from all segments of Bahraini politics met for the second session of a National Dialogue intended to hammer out a solution to the political crisis.
Talks among the 27 delegates are expected to last for months. An hour-long discussion in Wednesday night's five-hour session centred on the terminology of the talks.
Pro-government groups insisted on calling the meetings a dialogue, while the opposition has consistently called for them to be negotiations with the government to yield a political agreement for change.
"We are looking for real reforms and real change, otherwise there is no use of this dialogue," said Abdulnabi Salman, general secretary of the opposition Democratic Progressive Tribune and a delegate at the talks.
Opposition groups have vowed to continue their pressure on the streets in coming weeks.
"We won't stop," said Hanan, a mother attending yesterday's opposition march. "We feel the momentum growing in the opposition day by day."
But Bahrain's justice minister, Sheikh Khaled Al Khalifa, who is also coordinator of the national dialogue, warned yesterday that opposition protests would not influence the talks.
"The government will not permit the use of violence to pressure negotiators," Sheikh Khaled said.
"Whoever claims to be serious and real should not incite violence."
* With additional reporting by Agence France-Presse