It happened just before 3:30 p.m. on Freemansburg Avenue near 13th Street, the department said.
The victim and her 89-year-old husband were headed east in their Chevrolet when a westbound Subaru crossed lanes and collided with their car, authorities explained.
The couple and the driver of the Subaru, a 20-year-old man from East Allen Township, were all rushed to Saint Luke's Anderson for treatment, officials wrote. The 84-year-old woman died that day, police said, while the condition of her husband and the other driver were not immediately clear.
The victim's identity will be released by the county Coroner's Office, which did not immediately return Daily Voice's request for comment.
Meanwhile, investigators are asking any potential witnesses to the crash to step forward. Tips can be submitted to Sgt. LaPointe of the BTPD at 610-814-6481.
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