Pro-European integration protesters clash with Ukranian riot police during a rally near government administration buildings in Kiev January 19, 2014. [Photo/Agencies]

KIEV - Ukrainian protesters attacked riot police with sticks, fireworks and smoke bombs in central Kiev on Sunday, triggering another wave of clashes between officers and demonstrators.

According to the local media reports, the protesters have tried to overturn one police bus and torched another interior forces vehicle, which met with strong resistance from the police.

No causalities in the clashes have been officially confirmed so far. However, witnesses reported about dozens of ambulances at the site of protests in the heart of Ukrainian capital.

Ukrainian police has opened a criminal case into the incident.

The new wave of protests in Ukraine came after the parliament on Thursday approved the legislation, which bans some type of demonstrations. The new bill was widely seen as "anti-protests law" and sparked public criticism.

The protests started on Nov 21 last year with peaceful demonstrations demanding the country's European integration, but soon snowballing into a violent nationwide movement against authorities.

Furious at both the government's decision and the violent dispersal of earlier demonstrations, the protesters are demanding the impeachment of President Viktor Yanukovych, resignation of the government and disbandment of parliament.

Ukraine pulled out of signing a partnership agreement that would deepen its ties with the EU at the Eastern Partnership Summit in the Lithuanian capital of Vilnius last November, triggering the protests.