the cocaine was seized by u.s. and canadian forces in 19 separate incidents in the eastern pacific ocean near central and south america .
it included a 10 1/2 - ton bust from a coastal freighter , the largest maritime drug interdiction in that area since 2009 .
u.s. navy and coast guard and royal canadian navy ships have seized more than 28 tons of cocaine valued at $ 848 million in the last six months .
authorities have called it the most successful run for drug seizures in the area since 2009 .