A weekend drug bust at the Queenston Lewiston bridge netting U.S. Customs officials 1.5 tonnes of pot.
Border officials say the pot was hidden in shipping boxes labelled as zinc oxide.
The drugs have an estimated street value of $5.3 million.
This is the third major drug smuggling bust of the summer, border agents found a total of $37 million dollars worth of marijuana in two separate busts on the Peace Bridge, one earlier this month the other in June.