Video has emerged showing a Bulgarian vigilante group ordering three tied-up Afghan nationals to go “back to Turkey” after they crossed the border.
The restrained men can be seen handcuffed, lying face down as the vigilantes stand over them – one man can be seen holding a machete.
The ‘citizen’s arrest’ took place in the mountainous area of Strandja, on the border with Turkey.
Bulgarian authorities have launched an investigation into the incident and one man has been arrested.
Focus Information Agency reports that Petar Nizamov is accused of the “illegal arrest of three Afghan nationals”.
“A knife was found inside the vehicle, while at his home - a machete, a gas pistol, ropes used to tie the migrants, camouflage clothes and small amount of drug substances.”
Bulgaria’s Prime Minister Boiko Borisov initially praised the vigilantes, insisting that protecting the country’s borders was a joint effort.
Following a backlash from human rights groups, Mr Borisov retracted his comment.
In a Facebook post, he wrote: "Society should not be indifferent ... but rights shouldn't be exceeded. Any illegal or inhumane attitude will not only not be tolerated but will also be prosecuted under the law.”
A spokesperson for the United Nations refugee agency (UNHCR) told the Independent that “only the border police should be patrolling the border.”
“People who want to file asylum claims should be allowed into the country to do so. Their claims should be heard by the authorities in an orderly process - the refugee status determination procedure.”
“Ordinary citizens should not make an on-the-spot decision about whether someone is a refugee.”
The incident has also been decried by senior officials in Bulgaria.
Chief Public Prosecutor, Sotir Tsatsarov, said: "It is absolutely inadmissible for groups, separate individuals, squads, organisations or whatever they call themselves... to try to seize the functions of state institutions.”
"All such attempts will be prosecuted.”
Interior Minister Rumyana Buchvarova wrote on Facebook: "Today we must be careful not only of illegal border crossings, but also of those who want to benefit from them. For money or for cheap and dangerous glory.”
“There is nothing but the competent authorities, who can decide what's appropriate when it comes to refugees.”
Vigilante action in Bulgaria has increased this year as the refugee crisis continues to grip Europe.
Dinko Valev, a semi-professional wrestler, was dubbed a “superhero” by a Bulgarian television channel after “hunting” migrants on the border while riding his quad bike.
Tensions have grown in the country with the arrival of 30,000 migrants in 2015. Border police say they have detained around 10,000 migrants from Syria and Afghanistan in the first three months of 2016.
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