The European Commission expressed "dismay" Wednesday at reports of Belarusian police using clubs to break up a protest by opposition forces, saying such violations of human rights jeopardized plans to create closer ties between Minsk and Brussels, according to dpa. In a statement, External Affairs Commissioner Benita Ferrero- Waldner also called for the "immediate and unconditional release of those arrested" during Tuesday's demonstration. "It is unacceptable that peaceful demonstrators, including journalists, were reportedly arrested and some subjected to violent treatment. Such actions directly contradict the fundamental values of freedom of expression, and freedom of assembly, and we should all demand the immediate and unconditional release of those arrested while demonstrating peacefully," the commissioner said. Ferrero-Waldner said she was particularly dismayed by the fact that the events took place in the wake of what had been regarded in Brussels as a number of positive moves by the Belarus government. These include the release of a handful of political prisoners and final preparatory steps for the opening of a commission delegation in Minsk. "The Belarusian authorities must understand that the positive momentum created by these acts needs to be confirmed if we are to engage in a full partnership," she said. The European Union has offered to establish closer ties with Belarus, but only if the country takes "convincing steps towards democratisation, respect for human rights and the rule of law", the commissioner said. "That offer remains open," she added. According to reports, armoured troopers from the OMON anti-riot police tore into a crowd of some 4,000 people during the Tuesday evening protest. Wholesale arrests of participants and journalists covering the incident were reported. "Long live Belarus!" and "Free (Aleksander) Kozulin!" were among the most common chants heard. Kozulin is an opposition leader sentenced to 60 months' hard labour after similar protests in 2007. The March 25 demonstration is an annual event originally intended to mark Belarus' short-lived independence in the wake of World War One, before conquest by the Soviet Union. Belarusian President Aleksander Lukashenko, a supporter of the Soviet Union, has spoken out against March 25 demonstrations as disloyal to the Belarusian state, making the gathering a traditional face-off between opposition forces, and police.