SKOPJE, North Macedonia (AP) — Ten men were arrested in North Macedonia on Thursday, accused of running a smuggling ring that brought in migrants from neighboring Greece.

The Macedonian nationals, including a father and son who police say were the ringleaders, allegedly brought at least 100 migrants from the Middle East and elsewhere into the country over a 10-month period. The migrants had hoped to continue from North Macedonia through the Balkans to more prosperous European countries.

Police spokesman Toni Angelovski said most of the migrants were from Afghanistan, Pakistan, Syria, Iran and Egypt, and had all previously lived in Greece.

The ring allegedly operated a network of transit houses in four cities, including the capital, Skopje. It allegedly charged each migrant 700 euros ($825) for the trip.

If tried and convicted, the suspects face sentences of up to 13 years in prison.

The Greek border with North Macedonia has been closed for months because of the pandemic, but trafficking networks remain active.

Police say border authorities have prevented nearly 25,000 attempts by migrants to illegally enter North Macedonia from Greece in the first nine months of this year.