Avery Armknecht, 19, was charged with attempted criminal homicide, robbery, aggravated assault.
Armknecht, of Norristown, was seen on surveillance video entering the Mr. Cigarette store on West Cheltenham Avenue around 12:55 p.m. with a pocketknife and telling the employee to open the register., according to Cheltenham police.
He held the knife to the woman's throat and a struggle ensued.
Armknecht then stabbed her multiple times in the chest and fled westbound in a Nissan Altima, authorities said.
The 62-year-old woman was taken to a local trauma center, where she underwent emergency surgery, police said.
She is expected to survive.
Armknecht surrendered to police on Monday. He was remanded to the Montgomery County Correctional Facility with bail denied.
His preliminary hearing is set for Oct 21.
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