Husband Kills Wife After Snapping During Cruise

08/31/2017 04:01 pm EDT

Kristy Manzanares and her husband, Kenneth Manzanares, were celebrating their wedding anniversary on a week-long cruise from Seattle to Alaska last week. During the trip, he "snapped" and allegedly killed his wife of 18 years.

On July 25, Kristy, 39, was found lying on the floor of her cruise ship cabin. She had suffered a severe head wound and was pronounced dead by medical personnel minutes later, PEOPLE reports.

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Her alleged killer was her husband, Kenneth, also 39. The two met in high school and were celebrating their anniversary along with their daughters and extended family on a Princess Cruises voyage.

The murder allegedly happened after marital tensions between Kristy and Kenneth erupted when he became belligerent at dinner, according to a family source.

"He had been acting terrible all night," the source said.

At some point that evening, Kristy asked for a divorce. After hearing his wife's request, Kenneth allegedly "snapped" and killed her.

The family source explained that the discord between Kristy and Kenneth was not openly apparent to everyone.

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"If they were having [marital issues] they never showed any of that to anyone else," the source said.

On the night of the murder, Kristy's father and brother broke down the cabin door after hearing her scream. The two reportedly found Kristy mortally wounded with Kenneth being covered in blood.

Aboard the cruise ship, several passengers described hearing the couple argue before Kristy began "screaming for her life."

One particular guest that heard the commotion was two floors above the site of the incident.

"There was a lot of yelling started up again between men, fighting you know, somebody hurt somebody's sister and it was a family dispute," passenger Charles Rowlen said.

The arrest affidavit says that Kenneth allegedly told one witness, "She wouldn't stop laughing at me."

"I have my doubts that she was even laughing at him. Because everyone else said they heard fighting and yelling, not laughter," a family member commented.

The tragic incident has been hard for Kristy's family to handle.

"We are devastated over the loss of Kristy," her family said in a statement. "She is the light of our lives — a devoted mother, daughter, sisterand friend. Kristy led by example with her giving heart and we are inspired by the legacy of kindness and optimism she has instilled in her children."

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