The autopsy conducted on the body of 21-year-old Canadian woman found inside a water tank atop a hotel building in Los Angeles has failed to give any clue on the cause of her death.

Since the results were inconclusive, further toxicological tests have to be conducted before it could be decided whether Elisa Lam, a student from Vancouver, British Columbia, was killed or if she fell inside the water tank by accident.

Lam was discovered inside one of four large water tanks in Cecil Hotel in downtown Los Angeles Tuesday, after guests inside the hotel complained of a low water pressure.

She went missing Jan. 31 under mysterious circumstances.

Police investigating the matter had hoped to get conclusive clues from the autopsy that would help determine if she was a victim of foul play.

"They didn't find any bullet holes they didn't find any stab wounds to my knowledge. So then you've got to go to the next step," Los Angeles County Coroner's spokesman Ed Winter told Reuters.

Further, tests would be conducted to find out if the woman was on any medication at the time of her death and her organs too would be studied to see if she was suffering from any medical issues.

Elisa Lam who was hoping to graduate from the University of British Columbia in 2016 was last seen in the hotel located at 640 S. Main St. She arrived in Los Angeles Jan.26 as a tourist. It is not clear why she stayed at Hotel Cecil and why she came to California. Her final destination was supposed to be Santa Cruz.

Police released a video taken in an elevator of the hotel last week, which showed Lam behaving strangely, pushing multiple buttons, peering repeatedly around the elevator and sometimes hiding in a corner.

The Cecil Hotel is a two-star hotel with 600 rooms. 

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