BALTIMORE (WJZ) — As schools statewide crack down on security, Baltimore City is dealing with another violent attack after a woman allegedly pulled a knife at a middle school.

Mike Hellgren details the response.

A school employee confronted the woman because she never checked in at the front desk. That’s when school administrators say she attacked.

The second violent encounter on a Baltimore City campus in a week happened at National Academy Foundation.

A woman was buzzed in to the locked doors of the prep building, where middle schoolers attend classes, but administrators say she failed to check in at the front office.

They say she was delivering a birthday cake to a relative when a school worker challenged her in the hall. She pulled out a knife, cutting the worker’s hands, and was later arrested.

It alarmed a grandmother of a student here who asked WJZ not to identify her.

“I feel fearful for my grandson also,” she said “I went in just now. You have to go through a procedure before he can come out, and I think it’s good.”

She’s concerned about outsiders gaining access to classrooms following the shooting in Connecticut.

“There is no explaining it away. It’s awful. It’s gut-wrenching,” she said.

School officials would not say why the person was originally buzzed in through the door and how it all escalated into a weapon being pulled.

It follows an attack on a seventh-grader at Calverton Middle School last week.  The student says adults, including another parent, were allowed onto campus, and beat her up as she ran an errand at the principal’s office.

“I don’t know what a parent can say to a child that this happened to.  There’s really nothing you can say,” said Angie Harper, whose daughter was attacked.

City schools’ CEO Dr. Andres Alonso urged vigilance to keep children safe, and school police have been more visible on campuses citywide.

“It’s a punch in the gut.  It’s a situation where every parent across the country is struck,” said Ken Trump, president of the National School Safety and Security Services. “We have to keep school safety on the front burner.”

Another incident happened Tuesday at Friendship Academy in Baltimore. A student came in with a plastic BB gun. It was never fired and taken without incident. That student now faces disciplinary actions.