Police arrested 14 people during the day's protests in the capital Sofia, which had been peaceful, Novonite.com reported.
A man participating in a blockade of the Eagles' Bridge attempted to set himself on fire, but was stopped by other demonstrators and the police, the interior ministry said.
Several groups of protesters had gathered outside the front of the National Assembly, and another 200 were at the back entrance to the building, FOCUS News agency reported.
The demonstrations marked the 35th straight day of anti-government protests sparked by the appointment of a Bulgarian media mogul, Delyan Peevski, to the chairmanship of the State Agency for National Security.
The appointment was rescinded, but protesters continued to call for the cabinet of Prime Minister Plamen Oresharski to resign because of its ties to oligarchs.