Two types of systems already exists on the ATC side of things. There are red stop-bar lights at each runway entry point. Pilots are trained never to cross a red stop-bar even if told by ATC. The controller has to press a button to turn the lights off, and they automatically come back on after 1 plane has passed the lights.
In larger airports with an automated system, the system monitors the runway occupancy and approach sector. If the runway is occupied or an aircraft is on final within a certain distance, the system throws an alert before the stop-bars can be turned off.
On top of that there is also an autonomous version of this system that will use red lights to indicate a dangerous runway status (e.g. aircraft on approach) at each entry point. And the other way around, an aircraft line up for takeoff (but holding) will get red lights if any of the entry points further down the runway are crossed. More here: https://skybrary.aero/articles/autonomous-runway-incursion-w...
I can't edit this comment anymore, but there has just been an update that the stop bar lights I describe above were out of service at the airport in this incident.
In larger airports with an automated system, the system monitors the runway occupancy and approach sector. If the runway is occupied or an aircraft is on final within a certain distance, the system throws an alert before the stop-bars can be turned off.
On top of that there is also an autonomous version of this system that will use red lights to indicate a dangerous runway status (e.g. aircraft on approach) at each entry point. And the other way around, an aircraft line up for takeoff (but holding) will get red lights if any of the entry points further down the runway are crossed. More here: https://skybrary.aero/articles/autonomous-runway-incursion-w...