Bulgarian authorities detained a group of 26 Syrian refugees in the district of Kyustendil near the border with Serbia early on Friday.
There were four children among the refugees, who were traveling in a minibus bearing a licence plate from Kuystendil, private bTV station reports.
The refugees were uncovered near the village of Lomnitsa, which is in the vicinity to the Oltomantsi border checkpoint.
The driver of the vehicle, who according to unofficial information was from the area of Dupnitsa, was also detained.
According to the investigators, there was another accompanying vehicle, which has not been uncovered.
The regional prosecutor's office in Kyustendil continues work on the case.