TRENTON, N.J. — Howard Barton Unruh, who killed 13 people as he walked the streets of Camden in a psychotic 1949 shooting spree that was the nation’s worst mass murder at the time, has died at age 88.

Camden County Prosecutor Warren W. Faulk said Unruh died Monday at 3:35 p.m. in a Trenton nursing facility after an extended illness.

Unruh had been confined in a state psychiatric hospital since the killings, which came to be known as the “Walk of Death.” Diagnosed as a paranoid schizophrenic, he confessed to the killings and was judged mentally competent but never tried for the Sept. 6, 1949, massacre.