Friday’s fatal shooting of a Transportation Security Administration (TSA) officer at Los Angeles International Airport has renewed the debate about posting armed guards at airport security screening stations. In the wake of the attack, security officials are discussing a variety of options — from arming some TSA employees to keeping armed police officers closer to checkpoints — in an effort to improve airport security.

After the 9/11 terrorist attacks, armed officers were commonly posted at airport screening stations; but over time, and as budgets tightened, airport police took on more of a patrolling presence. After Friday’s shooting, TSA administrator John Pistole said the agency would review how it works with airport police and discuss overall security with Congress.

Part of that discussion previously centered on how close to screening stations airport police officers need to remain while patrolling terminals and performing routine duties. LAX has roughly 400 police officers who are responsible for security of the airport, while TSA officials have said their primary responsibility is keeping guns and explosives off airplanes.