Anna Maria Island, Florida -- A trip off the shore of Anna Maria Island turned deadly for a married couple this week, and detectives need your help in the case.
Deputies say a woman died on Wednesday, days after she was injured when her husband threw her off of the jet-ski they were riding during an argument on Sunday, just off the shore of Passage Key Sand Bar.
They say it all started when the wife caught her husband cheating with another man.
"It started out as a domestic battery," said Manatee County Public Information Officer Randy Warren. But the investigation into 50-year-old Michael Doster has morphed into a death investigation and possible homicide, he said.
Deputies say Michael Doster and his wife, Pamela, went to Passage Key Beach. The area is "popular with boaters that like to take their clothes off," Warren said.
It's there that they say after a day of drinking, she saw her husband having sex with a man.
"Obviously, that can lead to a misunderstanding between a husband and a wife. So this elevated the dispute," Warren said.
Deputies say the Dosters were riding the jet-ski when Michael grabbed his wife by the hair and pulled her off the watercraft. This happened more than four times, before she hit her head.
Having had enough, she went back to the sand bar on her own, where she was was found with a bruise on her head, an arm and a swollen area near one hip.
According to an affidavit, Michael Doster was concerned he could not locate her in the dark and called 911. Manatee Fire Rescue, the Coast Guard and an aviation unit from Pinellas County joined the search for Pamela Doster, before she was found on the san bar.
Doster was arrested that night at Rod and Reel Pier for domestic battery. He bonded out of jail this week, but now deputies suspect him of killing his wife.
Pamela Doster died on Wednesday from her injuries, but not before telling first responders her story.
When contacted by phone, Michael Doster laughed after a reporter identified himself, and then refused an interview.
But Manatee sheriff's deputies still need your help.
"People who were out there on the key that day. Please come forward. Tell us what you saw," Warren said.
You can contact Manatee detective John Kenney at (941) 747-3011 x 2216 or Crime Stoppers at 866-634-TIPS.
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