Also playing a key role in the interdictions were the Navy's patrol gunboats (PGs).

USS Restless (PG-66), a patrol gunboat launched 21 February 1940.

On 23 January, she was placed in commission in ordinary for conversion to a patrol gunboat.

Originally classified as a patrol gunboat, PG-146, Coronado was reclassified as a patrol frigate on 15 April 1943.

Not to mention the entire Burmese Navy base upriver with even more access to fast patrol gunboats.

They were rated as patrol gunboats and commissioned as PA-1 to 4.

While laid up, she was classified as a patrol gunboat with hull number PG-37 on 17 July 1920.

The ship received the Philippine Navy Plaque of Merit on 2009, being adjudged as the patrol gunboat of the year.

The newly restored Tomas Batillo class is the 7th patrol gunboat that was recently refurbished and modernized since its purchase back in 2006.

The vessels serving with the US Navy were known as Action-class patrol gunboats.