The buildings, which also include the ministries of finance and labour, and Ljubljana City Hall, have not been evacuated, but samples of the suspicious mail have been sent for analysis, the Ljubljana police have said.

They have received suspicious mail alerts this morning, between 8:45 AM and 9:45 AM, launching standard procedures immediately, including cordoning off the buildings and calling in fire-fighters, an anti-bomb police unit and Veterinary Faculty staff.

Samples have been sent to the Microbiology and Parasitology Institute of the Veterinary Faculty for analysis with results expected later today, the Ljubljana Police Administration said.

While the offices affected were not evacuated, the staff who have been in contact with the letters have been isolated.

Mail containing suspicious white powder has also been received by the Koper city municipality.