FORT WORTH, Texas (CBSDFW.COM) – Parents at a Keller ISD high school are becoming frustrated after multiple threats were made to the school within a week. A picture of a gun in a backpack sent the school into lockdown Wednesday afternoon.

Hundreds of parents took their children home after the lockdown was lifted during latest incident at Timber Creek High School.

The school sent out several tweets to reassure parents and students, but many families are still feeling on edge.

One of the tweets read in part: “Please know that we are working with all groups to make sure you feel safe on campus.”

A boy is facing a charge for making a terroristic threat. Authorities say he didn’t have a weapon on him.

Timber Creek High School officials say Wednesday’s incident is not related to two threats made earlier in the week. A verbal threat was made on Monday, and a video was released on Tuesday of students crowding around someone reported to have a gun.

One mother says her son reported one of the threats made this week and is upset that this happened again.

“We need to love out kids enough to not put them in this situation, whether that’s more security in schools, or I don’t know, just decent conversation,” said parent Erika Holbert.

The district says extra security will be added to the school after Wednesday’s incident.