Italian police have arrested four people in Palermo suspected of belonging to an international child kidnapping ring.

According to a police statement, the organisation abducted contested children of separated parents involved in custody battles.

Police said the group, whose members also included former soldiers who organised real “paramilitary missions” and used commando-style tactics to carry out the abductions.

The four people arrested in Italy were three Italians, Antonino Barazza, Luigi Cannistraro and Sebastiano Calabrese and a Ukrainian, Larisa Moskalenko.

Moskalenko, who owns a luxury boat rental in Palermo, is suspected to have supplied boats used for crossings from North Africa to Europe.

Another three suspects, two Norwegians and a Swedish national, were held in Tunisia as part of the same police investigation.

The first operation by the group took place in October 2012 when a child was kidnapped in Tunisia, sailed to Sicily and then transferred to Norway, the police said.

More kidnapping operations were being planned in Cyprus, Lebanon, Egypt and Ukraine, according to police.