Police in Bahrain have fired tear gas and clashed with students in a raid on a secondary school in the capital, Manama, reports say.
Officers stormed the Jabreya school for boys after students staged a protest demanding the release of a colleague arrested on Monday, activists say.
About 100 people have been arrested this month amid growing tension ahead of Sunday’s F1 Grand Prix in Bahrain.
The kingdom has been rocked by anti-government protests since early 2011.
The latest incident comes a day after a car bomb blew up in Manama, though without causing injuries.
An opposition group calling itself the February 14 movement has said it was behind the blast.
Activists tweeted pictures purporting to show clouds of tear gas at Jabreya school, with people wincing and covering their faces.
Images also showed dozens of spent canisters of tear gas and stun grenades. Unconfirmed reports said there had been injuries.
One father, Mohamed Jaber, went to the school to collect his son but was told by police to leave, the Associated Press news agency reported.
The clashes erupted when police went to break up a protest calling for the release of 17-year-old Hassan Humidan, who was arrested at the school on Monday.
Activists and protesters have called for the Grand Prix to be called off because of Bahrain’s human rights record.
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