New Charge for Man That Stabbed Great-Grandparents with Pocket Knife

20 year old Lucian Adrian Johnston has had another charge filed against him.  This time, the Harris County Sheriff's Office has charged him with possession of a prohibited weapon in a correctional facility after they located a second knife on his person. Harris County Sheriffs Office Inspector General is now conducting an internal investigation.

As a result, an additional $40,000 was added to his bond amount.  His total bond is now sitting at $240,000.

Johnston was already facing two charges of aggravated assault with a deadly weapon after attacking both of his great-grandparents earlier this week.

Sunday night, Johnston was sitting in the back seat with his half-brother while his great-grandparents drove him to a friend's house.  According to reports, a verbal argument ensued when the great-grandparents expressed concern about his "behavioral issues" and informed him that he would not be allowed to return to their home until he was evaluated by a doctor.

That was when Johnston is reported to have pulled out a pocket knife and began stabbing his great-grandparents in the head and neck.

His 12 year old half brother Sacha told ABC that he grabbed Johnston from behind and pulled him backwards, away from his 92 year old grandmother.  During the scuffle in the back seat, Sacha said that he grabbed the knife and even at one point held it against Johnston's throat.  He then said that Johnston pulled his finger back and headbutted him, loosening one of his teeth, in order to get away.

Johnston exited the vehicle and fled the scene on foot once the vehicle came to a stop, and Sacha threw the knife out of the car.

Sacha's 76 year old great-grandfather and great-grandmother were able to transport themselves to the hospital where they were treated for their injuries.  They were released Monday night and are expected to make a full recovery.

Johnston was located Monday morning and taken into custody without incident.  According to reports, he was scheduled to appear in court Monday night, but didn't make it as he is undergoing mental health evaluations.

Johnston's court date is scheduled for February 20th.