MADRID (AP) — A Spanish official says police are trying to refloat a submarine believed to be carrying a major cargo of cocaine.

If the cargo is confirmed, it would be the first time a submarine has been detected in drug trafficking to Spain, said the official from the government’s office in the northwestern province of Pontevedra on Monday.

Spain’s northwestern inlets have long been used to smuggle cocaine form South America into Europe.

Two Ecuadorians were arrested on land Sunday after police moved to seize the submarine in an inlet close to Pontevedra. Spain, in coordination with other countries, had been monitoring the submarine’s journey for some time.

The official said police can’t confirm the vessel’s cargo until they refloat it.

He spoke on condition of anonymity in keeping with government rules.