Authorities say Alexandra Fröhlich, age 58, was likely shot between midnight and 6 a.m. Tuesday morning, April 22, in Hamburg, Germany, according to the Guardian and German broadcaster NDR.
She was found by her son, according to police.
The boat is situated along the Elbe River in the eastern district of Moorfleet.
"Investigators are currently investigating possible suspects," Hamburg Police said in a statement. "However, due to the ongoing investigation, no further details can be provided at this time."
Meanwhile, divers are searching the river for a potential murder weapon.
Fröhlich wrote such renowned books as Death is Certain and There's Always Someone Dying, both of which first sold in 2016, and Skeletons in the Closet in 2019. The books were published by Penguin Random House.
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