A much-criticised ban on all demonstrations and public gatherings introduced in Bahrain this week appears to have fallen on deaf ears.
Pictures uploaded on social media are believed to show protesters clashing with police in the capital Manama on Thursday night.
Unrest has resumed despite a government crackdown following last year’s uprising among the majority Shi’ite population against the Sunni ruling family’s hold on power.
The latest trouble came on the day an activist was given six months jail for allegedly insulting the monarch on Twitter.
Two policemen died in attacks last month. Activists accuse security forces of using shotgun pellets against protesters.
The authorities say the protest ban is a temporary measure until security and stability are restored.
It has been denounced by Western governments, the UN Secretary General and Amnesty International.