Story highlights Atlanta woman killed in Grenada died of skull fracture, asphyxiation, police say

Jessica Colker, 39, was walking on the beach with her husband when they were attacked

A man is in custody in connection with the killing; police say he's cooperating

(CNN) American tourist Jessica Colker died from an "extensive skull fracture and asphyxia," according to autopsy results the Royal Grenada Police Force released Tuesday.

Colker, 39, was killed Sunday after being attacked by a man with a machete while walking with her husband along the beach just before noon, Sylvan McIntyre, assistant superintendent with the police force, told CNN.

A suspect is in custody in connection with Colker's death and is cooperating with police, McIntyre said. There are no charges at this time, and police will not release his name, photo or criminal record, he said.

Colker's body was later found on the beach, near where she was last seen, police said. McIntyre told CNN that it was his understanding her husband was unharmed.

Officials did not disclose a motive in the attack.

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