JOLIET, Ill. — The Joliet Police Department announced Wednesday an increase in police presence at all schools for the rest of school year in response to the mass school shooting in Texas.

A Texas official says an 18-year-old gunman who killed 19 children and two teachers at Robb Elementary Tuesday barricaded himself inside a classroom, “shooting anyone that was in his way.” 

Police and others responding to the attack also went around breaking windows at the school to enable students and teachers to escape, Lt. Christopher Olivarez of the Texas Department of Public Safety said on NBC’s “Today” show.

Olivarez told CNN that all of the victims were in the same fourth-grade classroom.

In a tweet Wednesday, Joliet police said they are “closely monitoring national events regarding tragic and unnecessary school violence.” They also said that there’ll be an increased of police presence at all Joliet school within the jurisdiction for the rest of the school year.