Croatia has admitted for the first time that it carried out the violent pushback of migrants trying to enter the country after an investigation exposed the conditions asylum seekers faced.
Video showed uniformed men with batons beating people trying to enter Croatia, and with it the EU, from Bosnia.
Police chief Nikola Milina said three members of an intervention unit have been removed from duty and are facing further disciplinary procedures.
“We don't want any such incident tarnishing the image of the Croatian police and the good work it conducts in border control and fighting migrant smugglers,” Mr Milina said. “It is our duty to get to the bottom of this.”
“We don’t want any individual case to influence the praise that Croatian police have received for protecting the outer borders of the EU, as well as other duties,” he added.
Greece has also promised to investigate reports of similar action by its officials.
Migration Minister Notis Mitarachi said he has told EU home affairs commissioner Ylva Johansson that the claims would be investigated.
“Every claim made is investigated by the judiciary and by our internal audit,” he said.
Croatia’s announcement came two days after the publication of video footage filmed during an eight-month investigation between journalists at different European news organisations, spearheaded by the non-profit group Lighthouse Reports.
Human rights groups have for years accused Croatia’s police of brutality and illegal pushbacks of migrants into Bosnia. Croatia, until now, has consistently denied the allegations.
The new video showed uniformed men in balaclavas beating groups of migrants at a porous segment of the country’s 1,000-kilometre border with Bosnia.
Bosnia became a stopping point for thousands of Europe-bound migrants from the Middle East, Central Asia and North Africa several years ago when other nations closed their borders to block migration paths through the Balkans.
Upon entering Bosnia, most migrants walk north-west to the border with Croatia, one of the last gateways to central and northern Europe.
Croatian Interior Minister Davor Bozinovic also described the incident as “unacceptable behaviour”.
The EU’s Ms Johansson said EU countries needed to protect the bloc's external borders, but that they also had to uphold the rule of law and fundamental rights.
Under international law, migrants have a right to claim asylum and it is forbidden to send potential asylum seekers back to where their lives or well-being might be in danger.