MADRID (AP) — Spanish police say they have arrested 57 people and dismantled an illegal immigration ring giving Chinese citizens Spanish residency permits through fake job contracts as domestic staff.

The Spanish National police said Saturday the arrests took place in Barcelona, Valencia, San Sebastian and Las Palmas, one of the Canary Islands.

Police said the Chinese citizens paid the smuggling ring about 8,000 euros ($8,960) for each fake contract. The ring paid between 1,500 and 2,000 euros ($1,680 to $2,240) to each contract sponsor, usually hotel workers in the Canary island of Lanzarote.

The police say the Chinese lived illegally in Spain, working in the textile industry in Barcelona.

According to the National Statistics Institute, Chinese immigrants are the fifth biggest foreign community in Spain with almost 170,000 people as of 2015.