DEKALB, Ill. (CBS) — Students at Northern Illinois University on Tuesday got their first look at the renovated Cole Hall, nearly four years after a massacre left five students dead.

The building, the full name of which is Fay-Cooper Cole Hall, has not been used since gunman Steven Kazmierczak, 27, opened fire during a geology lecture there on Feb. 14, 2008.

READ MORE: Chicago Police Officer Released From Hospital After Being Shot In Shopping Center Parking Lot At North And Sheffield Avenues

LISTEN: WBBM Newsradio’s Regine Schlesinger reports

The building went through a $6 million renovation, and now includes new labs and a beautiful new auditorium.

The lecture was in progress when Kazmierczak set a guitar case on the floor, pulled out a gun, and began shooting.

READ MORE: Chicago Weather: Pleasant Parade Weather Tuesday

Five people were killed in the incident – Catalina Garcia, 20; Julianna Gehant, 32; Ryanne Mace, 19; Daniel Parmenter, 20; and Gaybe Dubowski, 20. A total of 21 others were injured.

Kazmierczak shot and killed himself before police arrived on the scene.

He had attended NIU previously, but at the time was doing graduate work at the University of Illinois at Urbana-Champaign. He had purchased the firearms he used in the shooting legally in Champaign.

A school spokesman calls the renovation a sign that NIU is moving forward.

MORE NEWS: More Than A Third Of CPD Staff Missed Vaccine Reporting Deadline; City Could Begin Placing Employees On 'No Pay' Status Today

Following the shooting, then-Gov. Rod Blagojevich proposed that Cole Hall be demolished, but the idea was later rejected.