Sea soldiers are slightly different from RPs, who mainly just
guard a camp's compound.
Sea soldiers come under the Navy's control and guard the waters
surrounding a naval base/military area. These are restricted waters
up to several hundreds of meters to prevent terrorism or foreign
intrusion (eg. speedboat with explosives ramming against our naval
vessels, intrude into our base).
In daily routine operations, they conduct patrols and are
routinely activated to intercept boats that stray too near
restricted waters, ordering them to leave or risk being fired upon
or arrested. They also man the machine gun atop towers near
restricted waters. They are armed with live ammunition and may fire
upon intruders who try to force their way.
On a normal peacetime day, they will just give verbal warning
with siren and shoo away any curious/wandering boats.... only
against persistent intruder will they fire their weapons.
http://www.youtube.com/watch?v=YB1O2-pRo-0