The Mesa Police Department has arrested a woman accused of viciously attacking a substitute school bus driver last week. The suspect, Hermenegilda Marquez, 27, faces aggravated assault charges after the incident, which occurred at a bus stop near McKellips Road and Country Club Drive, azfamily.com reports.

The altercation took place shortly after 2 p.m. on April 11 when Marquez allegedly approached the school bus and accused the 64-year-old driver of making statements about her daughter. According to the victim, who does not regularly drive that route, she was unfamiliar with Marquez and her child and denied the accusations. FOX 10 Phoenix detailed that Marquez's response was to physically assault the driver, culminating in an assault that left the woman with a red mark under her right eye.

Authorities arrived on the scene to find the driver "visibly upset and crying," as well as the children still on the bus. Court documents reveal that the surveillance footage from the bus shows Marquez boarding, initiating a confrontation, and then physically attacking the driver, including slapping and hitting her with closed fists. During this brutal exchange, the victim's pacemaker began to shock her, adding a layer of physical distress to the altercation. The suspect's boyfriend is also seen on the video, entering the bus to pull Marquez away from her assault.

Marquez was apprehended this Wednesday, whereupon she was shown the surveillance video and informed that she would be charged with a felony. Officers stated "she showed no emotion" during the revelation. The suspect, who is currently on unsupervised probation for a previous domestic violence assault conviction, invoked her right to legal counsel and refused to speak with investigators following her arrest.