High school classmate Alex Ristea, of Vancouver, called Lam's death shocking and said she was one of the friendliest people he knew.
"This is the last person I expect out of all my friends to have something like this happen to her," Ristea said.
University of British Columbia spokesman Randy Schmidt confirmed that Lam had attended summer school at the university, but she was not registered for the current session.
Ristea said he believes Lam had just gone to California for a holiday, saying she had posted pictures on Facebook from tourist locations such as the San Diego Zoo.
Reached by phone, a man who confirmed that it was Lam's home said he was busy and hung up when asked to speak about her. A woman reached later at the same number, when told it was a reporter calling, also hung up after saying, "Sorry."