Antoinette Pelzer, 45, who had been living in Philadelphia before winding up in Atlantic City, changed her plea to guilty to murder Friday at what was to have been just a status hearing, The Press of Atlantic City reported.
Pelzer faces the possibility of two consecutive life terms in prison when she is sentenced Oct. 24.
Pelzer admitted stabbing Alice Mei See Leung, 47, and her 80-year-old mother, Po Lin Wan, both of Scarborough, Ontario, with a butcher knife the morning of May 21, 2012 while attempting to rob them. The victims were strolling along Pacific Avenue, just a half-block from a hospital, when they were attacked.
Police officer Jacob Abbruscato spotted Pelzer within seconds while patrolling in the area and arrested her.
The newspaper said Pelzer's public defender had said in January her client had been diagnosed with schizophrenia in the past.