Apache helicopter down in Galveston Bay, Texas
 

A US Army Apache helicopter went down next to the Bayport cruise terminal near LaPorte, TX on Wednesday afternoon. It had departed on a training exercise from Ellington Field near southeast Houston.

Local television shows part of the aircraft inverted in shallow water near the shore with the undercarriage visible. Portions of the main rotor also appear to have been recovered in a field right at the shoreline.

FWIW, some eyewitness reports say there was a "bang" and the helicopter broke up in mid-air. USCG and local authorities are still involved in the recovery operation.

Regrettably, it does not look good for the two crew members aboard at the time.

Report with pix and video.

http://abcnews.go.com/US/wireStory/coast-guard-aboard-crashed-helicopter-galveston-bay-44439822

• By The Associated Press

LA PORTE, Texas — Dec 28, 2016, 10:38 PM ET

Texas Army National Guard officials say two crew members aboard an Apache helicopter on a routine training mission have died when their aircraft crashed in Galveston Bay just off the shoreline about 25 miles southeast of Houston.
Chief Warrant Officer 5 Glen Webb says names of the victims are being withheld until their relatives are notified.
The helicopter was based at nearby Ellington Field.
Witnesses said the aircraft broke apart in the air late Wednesday afternoon.
Debris and a small oil slick were on the bay. A piece of the chopper's blade was found on land near the crash site.
Divers were working into the night to retrieve the victims. The wheels of the helicopter poked above the water's surface about 25 yards from shore near a vacant cruise ship terminal.

Ouch. Broke up in mid flight? Keenly interested to see what the cause is.

RIP, gents, another "routine training mission" ends up with loss of brothers in arms. :(

EDIT: I looked through the photo gallery. That isn't just the blade that is detached from the helicopter. Still attached to it are what look to be parts of the hub and the blade grip/retention. (Terminology may be off due to me not being familiar enough with that aircraft's nomenclature for those parts). From the pictures of the blade and attached elements, I am wondering if the blade strap had a failure, or if something else failed and this blade, plus hardware, went one way and other parts went elsewhere with the main body of the aircraft ending up in the water. Cant find my old TM, nomenclature still probably wrong.
EDIT 2:
From this picture, I am not sure if that is showing a part of the mast attached or not. It does appear that one blade with attaching pieces is lying next to the fence, and the attaching bits without a blade are attached to all that.

The Dutch lost one in Mali last year due a "flight control component".
Component failure is cause of Dutch Apache crash in Mali

https://www.defensie.nl/english/late...1;-27-november

Doesn't say what the component was though.

That brings the total up to 5 I think... 5 fatal accidents resulting from main rotor component failures since ~2013. Not a good trend.