Teams of officers of the National Revenue Agency, the Customs Agency and the Bulgarian Food Safety Agency, have been inspecting border crossing points and big wholesale fruit and vegetable markets in the country since 4.30 am on Wednesday in an operation targeting cheap imports.

In Sofia, inspectors are checking the wholesale markets in the the "Slatina" and "Druzhba" residential districts, according to reports of Darik radio.

The inspectors are checking the origin, quality and safety of fruits and vegetables offered on the wholesale markets.

The operation is part of the set of urgent measures initiated by Agriculture Minister Dimitar Grekov to protect domestic agricultural production.

The inspections were triggered by a peak of protests of agricultural producers from the southern Bulgarian cities of Sandanski and Plovdiv, who have been staging roadblocks and throwing out fruits and vegetables on the road since the end of last week due to the lack of a market for their production and the low purchase prices.

Bulgaria's Ministry of Agriculture and Food is expected to come up with an official announcement on the mass inspections later on Wednesday.