Police in Trincomalee obtained a court ban against a protest march and briefly detained a Tamil activist on 30 August.
The agitation was planned to demand to know the fate of victims of enforced disappearances.
On submissions made by the OIC of Trincomalee headquarters police, a magisterial order to organizers of the protest said they should not hold the march and refrain from creating a clash.
According to correspondents, Tamil women who led the campaign walked to a memorial with the intention of paying floral tributes to their missing relatives.
Avoiding the main road, they then arrived in the beach and started a demonstration, shouting slogans.
There, police arrested Rajkumar Rajivkanth.
The women continued to agitate and after two hours he was freed.
The heads of the three eastern district associations for missing persons handed over a petition to Trincomalee bishop Noel Emmanuel to be forwarded to the United Nations.
Similar protests took place in Jaffna and Kilinochchi as well.
