A male and female companion left after dropping the 59-year-old woman off at the hospital just after midnight, Capt. John A. Faggello told Daily Voice.
"Emergency medical personnel immediately began CPR but were unsuccessful in their attempt to revive the woman and she was pronounced dead on arrival," the captain said.
Several hours later, detectives tracked down the couple and interviewed them, Faggello said.
"The cause of death is pending the results of an autopsy/toxicological screening," the captain said, adding that next-of-kin had been notified.
"At this time no foul play is suspected," he said, "but the investigation is ongoing."
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