Bahrain officials said a city hall was set ablaze during a night of clashes between police and protesters, following the execution of three men convicted of a deadly bombing targeting police.
Bahrain's interior ministry said on Monday that the fire at the Northern City Hall appeared intentional.
It said firefighters were able to contain it.
READ MORE: Bahrain executes three over police killings
Hundreds protested on Sunday over the execution by firing squad of three Shia men accused of the 2014 bombing that killed two Bahraini policemen and an Emirati officer.
Abbas al-Samea, 27, Sami Mushaima, 42, and Ali al-Singace, 21, were executed a week after a court upheld their death sentences over the 2014 attack, the prosecution said in a statement carried by the official BNA state news agency on Sunday.
Opponents of Bahrain's Sunni-ruled kingdom saw the men's charges as politically motivated and alleged that the men were tortured.
Seven other defendants received life terms.
Some youths threw gasoline bombs and clashed with police into the night on Sunday. Police fired tear gas and birdshot.
Demonstrators blocked roads with burning tyres and threw firebombs, and police retaliated by firing tear gas, according to posts on social media.
The confrontations continued overnight, with dozens of men and women marching through the streets of the village of Sanabis chanting slogans against the Al-Khalifa dynasty, according to witnesses.
'Dark day' for Bahrain
Demonstrators tried to reach the main street of Sanabis, the hometown of the three executed men, but were blocked by security forces.
Sanabis was the closest Shia village to the former Pearl roundabout which was the epicentre of a month-long Shia-led uprising that the security forces crushed in mid-March 2011.
Protests turned violent overnight in several other Shia villages, according to other witnesses who said police opened fire with buckshot to disperse demonstrators, wounding several.
Bahrain's authorities do not permit international news agencies, including Al Jazeera, to cover events independently.
The executions were criticised by international rights groups as well as Britain and the European Union.
In a post on social media, Human Rights Watch's Nicholas McGeehan called the executions "unjust and inflammatory.
"Public, unequivocal condemnation imperative to prevent Bahrain killing more young men," he wrote.
Amnesty International said the executions were carried out "after an unfair trial and despite claims from the men that they were tortured in custody", and condemned them as "a dark day for human rights".
Bahrain denies practising torture.
Bahrain's majority Shia population has for decades accused their rulers of discrimination in matters of jobs, housing and political say.
Source: News agencies