Spanish police have seized 1.5 metric tons (1.7 short tons) of cocaine aboard a South American ship in the northwestern region of Galicia and arrested at least nine people.

A specialized unit of National Police located the drugs aboard a fishing vessel from Venezuela on Monday, Europa Press news agency reported, citing police sources.

Although nine suspects were under arrest, an investigation was still ongoing Tuesday and more arrests were still possible, the report says.

Regional government and police offices could not immediately verify the details.