During the operation, a barrel was checked and found to contain the illegal firearms and ammunition.
A total of nineteen firearms and more than 400 assorted rounds of ammunition were recovered to include 13 handguns, 6 high powered rifles and 39 magazines.
Some of the bullets found
The barrel is said to have a Western Jamaica address, and arrived in the island recently from Florida in the USA.
There is now a major multi-agency investigation underway as the Police seek to identify the persons responsible.
According to head of the St. James Police Division, Superintendent Vernon Ellis, last year the St. James Division recovered 116 illegal firearms and 1,378 rounds of ammunition, which was the highest recovery made by any division.