The residents of the southwestern border village of Kulata claim that the first illegal migrants have already crossed from Greece into Bulgaria.

Over the weekend, children from the village noticed six-seven men carrying their luggage in bags who were walking on the international railway line.

The children told their parents that the people had spoken in a foreign language, with the foreigners making signs to the children to keep silence.

Adults from the village also noticed the group which quickly disappeared in the darkness, the Bulgarian National Radio (BNR) informs.

The signal was submitted to border police, but the authorities have not been able to locate the traces of the illegal migrants.

Despite the heightened security measures on the border with Greece, the residents of Kulata and the nearby villages claim that the guard is ineffective.

They are also concerned that former military barracks and border facilities are being intensively prepared to be turned into refugee centres in the event of heightened migrant pressure.

Last week, the citizens of Kresna protested against the alleged plans to turn the former military barracks in the town into centre for the accommodation of refugees.

Smuggling used to be profitable activity in the region and people who had been involved in it have started to be active on both sides of the border.

Local residents are firm that the erection of a fence could be the only effective measure in the event of a heightened migrant flow from Greece into Bulgaria.

Bulgarian Prime Minister Boyko Borisov and Defence Minister Nikolay Nenchev have said on several occasions that Bulgaria has readiness to erect a light wire fence on the border along Greece.

There are expectations for the refugee flow to be redirected through Bulgaria with the closure of the Western Balkan migrant route.

Bulgaria's border police and army have been conducting joint drills in order to maintain the readiness of the country to guard its borders.