According to figures from the unions, some 6 000 teachers protested on September 1 in Sofia.

Protests started by circling the building of Bulgarian National Bank (BNB). Later on traffic on boulevard Dondukov was blocked by the protesters. When the traffic on the boulevard was lead around the protests, teachers returned to the BNB building, Focus news agency said.

Around 1 500 signatures had been collected in support of the teachers' protests. The signatures would be presented to parliament, Focus said.

The strike committee demanded negotiations with the prime minister and education and finance ministers. "The lack of dialog escalates social tension and provokes a different kind of civil protests. The decision by Education and Science Ministry to block the money of teachers on strike, calls for extreme reactions," teachers said.

Teachers have been on an effective strike as of September 24, demanding a gradual salary increase of 100 per cent.

Today nine schools in Sevlievo had joined the strike and at least five protesters were in hunger strike, Focus news said.