What are the possible reasons for fish to die and wash up on shore?

Mostly reef fishes and this has been happening every day for a few months now.

I haven't seen them except in photographs,but I do not think it is due to an oil spill.As far as I know there hasn't been a (big) spill in recent history,but as it is the ocean and boats being common I am sure there are small amounts present.

Experts are being brought in for investigation of this phenomenon,but until then I would like to know what you think are the possibilities.
Anyone who could shed light on this will be much appreciated.

Thank you.

An excerpt from the local paper...
"Although a huge variety of reef fish have been reported as dying the prevalent species, almost 98 percent, that are dying are the red-toothed triggerfish, a dark blue bodied fish, ranging up to 50 cm in length. It inhabits open waters and current-swept seaward reefs between 0 to 35 metres (0-115 feet) and can often be seen in groups turning and circling just under the sea surface while feeding on plankton brought in by the current."

It could be bacteria, an infectious kind of thing, it could be cold or hot water dumping, chemicals, a nmber of things. What are red-toothed riggerfish sensitive to?

Hey Charlotte,
I am not sure what they are sensitive to...

Is there evidence of a red tide?

They say the waters have a lot of mercury and there is off shore oil spills and chemicals.

This site has a lot of stuff about the bees and animals mysteriously dying.
She has been studying the bees over a year before it ever was on the news.

Earthfiles.com Search (http://www.earthfiles.com/search.php?query=fish+&table=NEWS&boolean=AND&sYear=1998&sMonth=01&sDay=01&eYear=2007&eMonth=12&eDay=08&Submit.x=14&Submit.y=6)

Is there evidence of a red tide?

Shy,
I am not sure if there are any evidence of a red tide.As far as I know there has not been any human casualties/skin irritations due to swimming etc.
There are algae growth differences during the monsoons,maybe it has been affected by global temperatures or maybe the Tsunami had an affect on it.

I was also thinking of the possibilities of a rise in the temperature of the earths core.Maybe frequent earthquake and volcanic activities in the Asian region is affecting the ocean temperatures or currents.
These are just theories off the top of my head,nothing concrete has been found yet.

NoH4,
Thanks for the link.

Could it be a bacteria or something with the plankton?