LOS ANGELES (CBSLA.com)  — The death of a 21-year-old Canadian tourist who was found in a downtown LA hotel’s rooftop water tank has been deemed an accidental drowning.

Elisa Lam of Vancouver, British Columbia, had been missing since Jan. 31 — about five days after she arrived in the Southland.

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Her whereabouts remained a mystery for more than two weeks. On Feb. 19, about 10:15 a.m., a maintenance worker checked the tank after guests of the Cecil Hotel (640 Main Street) complained about low water pressure.

Surveillance video from a hotel elevator showed Lam acting strangely. At one point the video showed Lam — who had been a guest at the hotel — pressing all of the elevator’s buttons and stepping in and out of the car.

Her family said she was on a stopover in LA on her way to Santa Cruz.

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Public health officials assured hotel guests that the water in the building was not tainted because of Lam.

Hotel employees said roof access doors were locked and had alarms, but the four water tanks were not locked, police said.

The roof was searched after Lam was reported missing, but it was unclear whether the tanks were checked, according to police.

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