NEW YORK (AP) — New York City police say a woman who went to prison for killing a relative has been stabbed to death by her boyfriend.

Katherine Seeber was released from state prison in July after serving 12 years for killing her step-great-grandmother, 91-year-old Ruth Witter. Police accused Seeber and her then-boyfriend, Jeffrey Hampshire, of strangling Witter during a botched robbery in Albany in February 2000 and then dumping her body near a national park in rural Saratoga County.

Seeber pleaded guilty to manslaughter and was sentenced to 20 years to life in prison. Hampshire was acquitted.

Police say 38-year-old Pedro Sanchez killed the 31-year-old Seeber Tuesday in her Queens apartment.

Sanchez, who police say is homeless, is charged with second-degree murder. It couldn't initially be learned if he has a lawyer.