Sylvia Seegrist shot ten people at the Springfield Mall in Delaware County, Pennsylvania on October 30, 1985, killing three of them. This is a single rampage on one afternoon, and it is flagged as one incident rather than a series.
She was born in 1960 and had a long documented history of schizophrenia, with repeated hospital admissions and a record of threatening behaviour that had been reported to police before that day. She walked into the mall in combat clothing with a Ruger .22 semiautomatic rifle and opened fire. Recife Cosmen was two years old, Augusto Ferrara sixty-four, and Dr Ernest Trout sixty-seven. Seven more people were wounded. A shopper who thought the rifle was a toy took it from her.
In June 1986 she was found guilty but mentally ill, and was sentenced to three consecutive life sentences, one for each person killed, and seven consecutive ten-year terms, one for each person wounded.