DAKAR (Reuters) - Senegal has seized 798 kg of cocaine hidden inside new cars on a ship traveling from Brazil, the customs authority said on Sunday, the latest in a series of large seizures off the West African coast this year.

It said the cocaine was discovered overnight inside 15 cars that the ship, which anchored at port in the capital Dakar, was transporting. The discovery follows the seizure last Wednesday of 238 kg of cocaine smuggled from Brazil in a similar manner through Dakar’s port.

Drug smugglers use West Africa as a transhipment point for cocaine en route from South America to Europe.

Last week, the U.N. Office on Drugs and Crime said 3.4 tonnes of cocaine were seized in Africa in 2017, back up to 2013 levels after falling to 1.2 tonnes in 2015, although the data likely underestimates the extent of drug trafficking on the continent.

Seizures in West Africa are on the rise this year, with several unusually large quantities intercepted.

In January, Cape Verde seized 9.5 tonnes of cocaine in one of the region’s largest ever hauls. Two months later, Guinea Bissau recorded its biggest seizure of cocaine when it intercepted 789 kg stashed away in a fish truck.

Senegal’s largest seizure came in 2007, when authorities seized almost 2.5 tonnes of cocaine worth more than $300 million.