Elisa Lam Update: Woman found in L.A. hotel's water tank accidentally drowned, authorities say

(CBS/AP) LOS ANGELES - Authorities say Elisa Lam, a Canadian woman whose body was discovered in a downtown Los Angeles hotel's rooftop water tank, accidentally drowned.

PICTURES: Official: Woman accidentally drowned in LA hotel water tank

Coroner's Lt. Fred Corral says the 21-year-old Lam's cause of death was ruled an accident on Thursday. Corral says the body had no sign of trauma indicating foul play. Lam also had bipolar disorder.

Lam traveled alone to Los Angeles from Vancouver, British Columbia, on Jan. 26 and was last seen five days later by workers at the historic Cecil Hotel near Skid Row.

Before she died, hotel surveillance footage showed Lam inside an elevator pushing buttons and sticking her head out the doors, looking in both directions.

Lam's body was found on Feb. 19 in the water tank after hotel guests complained of low water pressure. According to CBS Los Angeles, public health officials assured hotel guests that the water in the building was not tainted because of Lam.

The station reports hotel employees said doors providing access to the roof were locked and had alarms, but the four water tanks were not locked. It is unclear how Lam gained access to the roof.

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