Customs officials in Rotterdam have intercepted a huge shipment of highly toxic batteries being smuggled from the Caribbean to India.

Altogether 825 tonnes of disused lead-acid batteries were found in 33 containers originating in Jamaica and Puerto Rico.

They were on their way to India for processing but labelled as harmless plastic and metal waste. Shipping companies need permits to transport hazardous substances by sea.

The transport and environment inspectorate ILT said it would not allow the cargo to be sent to India “because of the risk of the batteries catching fire in transport if not handled properly”.

“We have never seen illegal smuggling of hazardous waste on this scale,” the ILT said on its website.

Lead acid was used in the earliest types of rechargable batteries, but is harmful to the environment, can cause brain and kidney damage and is prone to corrosion.

The ILT will discuss how to deal with the batteries with the governments of Jamaica and Puerto Rico, as international law requires illegal cargo to be returned to the country of origin.