Finnish guards working with EU border agency Frontex were involved with pushback practices that involved illegally repelling migrants at the EU's external borders, according to an investigative unit from Yle's Swedish language department.

Frontex is tasked with securing human rights at the EU border. Whistleblower and human rights groups, however, claim the agency has been complicit in operations to drive away thousands of migrants attempting to enter the bloc.

Yle's investigation found two border incidents involving Finnish border guards.

The first incident dates back to September 2016 at the Hungarian-Serbian border, when a dog - which was with a Finnish border guard that was part of a Hungarian patrol - bit a woman. The woman's injuries required her to be hospitalised and took eight days to heal, according to an internal Frontex report. The woman was not given the chance to apply for asylum in Hungary, but was sent to the Serbian side of the border.

The Hungarian Helsinki Committee, a human rights watchdog, said Hungary has deported 72,000 people in the past five years. The group's name is a nod to the OSCE meeting staged in Helsinki in 1975.

The second incident involving Finns took place in March of last year in the Aegean Sea, where a Finnish-staffed Frontex coast guard patrol stopped a migrant vessel before it reached the Greek coast. In line with Frontex protocol the Greek coast guard took over, asking the Finns to leave.

Pietari Vuorensola, a chief inspector with the international unit of the Finnish Border Guard, confirmed the incident at sea.

The EU agency has denied involvement in migrant pushbacks. Yle requested access to Frontex incident reports involving Finns since 2010. After three weeks the agency responded, saying three such reports existed but only one of them was not sealed.

Drawing on a number of other sources, Yle has however uncovered the details of the two incidents described.

While Interior Minister Maria Ohisalo (Green) said she has not heard of any incidents involving Finns, she noted that cases like this should be tried in court.

Earlier this autumn, Ohisalo told Yle that Finnish border guards must abide by both Finnish and EU laws.