Stink bugs originating from Japan are preventing thousands of vehicles being delivered to New Zealand.

New Zealand authorities assert that three large cargo ships carrying imported cars and machinery from Japan have been refused entry at ports this month due to the infestation of stink bugs onboard.

CNN reports that the bugs often reproduce quickly, eat various crops, and resist most pesticides (in case you need to know more, we’ve added a video below). They are a foreign pest would could seriously hurt New Zealand’s ecosystem.

The CEO of New Zealand’s Imported Motor Vehicle Industry Association, David Vinsen, says that the three ships were carrying more than 10,000 new and used vehicles.

“In my 15 years in this role, and probably 30 years involved in this industry, I have not seen anything which is as serious as this,” he said.

Alongside the vehicles waiting to be off-loaded in New Zealand, there are up to 8000 more vehicles awaiting shipment in Japan.

Due to the stink bugs, workers who help process the vehicles at the ports have had their working hours cut back and been told to take time off. Temporary lay-offs could follow in a matter of weeks, Vinsen said.

In an effort to ensure that no such infestation occurs again, the New Zealand government has introduced new laws. These rules will require all used vehicles from Japan to be cleaned and inspected at an approved facility before being shipped to the country.