The woman, whose name has not been released, succumbed to her injuries and died at the hospital later.
A quiet library in Middlesex stood still in time and horror as a man stepped in, followed an unsuspecting woman and stabbed her to death with a 10-inch long hunting knife.
Library patrons watched in shock as the suspect, 23-years-old Jeffrey Yao from Massachusetts town stabbed the woman on her head, chest and torso, the Washington Post reported.
Another 77-years-old man was stabbed in the arm as well as the people present rushed to the staggering woman’s help in a bid to stop the attacker. His injuries are minor.
The woman, whose name has not been released, succumbed to her injuries and died at the hospital later. Officials said they are waiting to notify her next of kin before making her name public.
The incident reportedly took place around 10:30 a.m.
Reasons for the attack remain unknown. Yao’s neighbours told the Boston Herald that his behaviour “was increasingly erratic,” while some added they were worried he "will kill somebody."
One neighbour who chose to remain anonymous claimed that Yao had tried to "smash our door down" at 3 a.m. in 2017. Another neighbour, Leslie Luongo said she was afraid of Yao and ‘would run to her car’ while leaving for work.
Ann Wirtanen, the library's director, announced that the library will be closed "until at least Tuesday,” in a statement posted on Facebook.
Yao has been arrested and charged with murder and attempted murder. He is being held without bail until his arraignment on Monday.