BNP activists allegedly snatched away two of their fellows from law-enforcers by vandalising a prison van in front of High Court on Tuesday afternoon.
Police said BNP men also broke two rifle butts of police when law enforcers tried to resist the demonstrators.
Sources said several hundred leaders and activists gathered around the High Court Mazar gate area in the morning as BNP Chairperson Begum Khaleda Zia was scheduled to appear before a court of Bakshibazar at noon for Zia Charitable graft case.
Police detained two BNP activists from the area and kept them inside a prison van under police guard.
When Khaleda Zia was returning her Gulshan residence through the area after appearing the Bakshibazar court in the afternoon, leaders and activists started demonstrating.
At one stage, BNP activists attacked on police and prison van in front of High Court.
Deputy Commissioner (Ramna Division) of Dhaka Metropolitan Police Maruf Hosain Sarder said they 'snatched away' the two detained BNP activists by vandalising the prison van.
He said rifle butts of two policemen were also broken by the demonstrators as they tried to prevent them from snatching two of their comrades, he said.
According to UNB, despite their attack on the law enforcers, police were patient and detained 69 leaders and activists from the area, the DC added.