UPDATE: According to Redstone Arsenal's Facebook page, Tuesday morning, a potential active shooter incident occurred at Redstone Arsenal, in the Sparkman Center. The installation was in lock-down mode with all gates closed, and employees sheltered in place at their respective buildings.

As of 12:30 p.m., employees can move about the post in an orderly fashion, but are asked to keep movements limited, as needed.

Movement remains restricted in the area near the intersections and roads around the Sparkman Center.

The gates to the Arsenal are open and operational.

This incident is under investigation. The safety and security of our workforce remains our top priority.

PREVIOUS STORY: A possible emergency situation is underway at Redstone Arsenal.

A spokesman for Redstone says it could be a possible active shooter. All gates are closed at this time.

The Marshall Space Flight Center sent an alert at 10:00a.m. Tuesday warning that a "situation exists near the Sparkman Center, RSA bldg. 5301."

The message asked for people to avoid the area.

A second message send at 10:30 reads: "An active shooter has been reported at the RSA Sparkman Center. Personnel in this area take protective action now. This is not a drill."

An active shooter drill was planned for tomorrow, however, officials tell us the current situation is not part of the drill.