Finnish police suspect that the Karf family, missing from Ostrobothnia, may be in hiding in Sweden, according to Aftonbladet.

Police base their suspicions on Sweden's geographic proximity and the close ties between the two countries, according to the paper.

The family of ten — the parents and their eight children — disappeared from Ostrobothnia just over two years ago. An international missing-persons alert has been issued for the children.

The Swedish newspaper interviewed Mikael Appel, spokesman for the Ostrobothnia police department, for its report.

That suspicion is also supported by the fact that the Karf family is Swedish-speaking.

Appel told Aftonbladet that police have reviewed footage from public surveillance cameras, but it remains unclear whether recordings from ferries and border crossings have also been analysed.

"Going through video material is extremely labour-intensive," Appel said.

When reviewing surveillance footage, investigators need to know which vehicle they are looking for and the approximate time of passage. In the case of the Karfs, that information is not available, he added.

Apple also said police have received nearly 400 tips in the case, which he described as exceptional.

"It is unlike anything I have experienced in more than 20 years of service. We expected a quick resolution and did not think such a large group of people could remain missing for so long," Appel said.

An Yle investigation found that a long-running dispute over homeschooling motivated the family's sudden disappearance. The parents allegedly sought to prevent their children from being taken into care and enrolled in the public school system.