Antoinette Pelzer is charged with two counts of murder. (CBC)

Two women from Toronto who were stabbed to death outside an Atlantic City casino on Monday morning, were mother and daughter.

Authorities in New Jersey were only able to release the identities of the two victims on Wednesday, after having difficulty locating their next of kin.

"On May 21, 2012, at approximately 10 a.m., Po Lin Wan, 80, and Alice Mei See Leung, 47, a mother and daughter from Scarborough, Ontario, were fatally stabbed multiple times ...," said a news release from Atlantic County prosecutor's office.

The prosecutor's office said next of kin were located in Hong Kong and that as far as they know there is no family in Canada. Authorities were unsure whether the pair were on a bus tour or traveling on their own.

Antoinette Pelzer, 44, of Philadelphia, has been arrested and charged with "two counts of murder, unlawful possession of a weapon, and possession of a weapon for unlawful purpose and robbery."

The prosecutors say Pelzer attacked Leung outside Bally's Atlantic City casino with a 30-centimetre butcher knife. Leung was stabbed multiple times in the upper body and died. Her elderly mother came to the aid of her daughter and was also killed.

"Ms. Wan was stabbed in her lower body, hand and shoulder while coming to the assistance of Ms. Leung," the prosecutor's office said in a news release.

Witnesses told police Pelzer allegedly tried to steal one of the victims' purses and that the attack appeared to be unprovoked.

Pelzer was arrested by a police officer who witnessed part of the attack.

According to her family Pelzer suffers from schizophrenia and had been homeless since January.

Gladys Pelzer, the defendant's mother, told WPVI-TV in Philadelphia that the stabbings apparently occurred while her daughter was trying to get money to buy cigarettes.

"I feel sorry about the people she hurt because all she wanted a cigarette. That's what this was all about," she told the TV station.