DEVELOPING: Active shooter at Houston hospital, massive police response underway

Houston police are responding to reports of an active shooter at Ben Taub Hospital in Texas Medical Center.

Patients were evacuated from the hospital as officers entered the building with guns drawn, according to KHOU-TV.

Baylor College of Medicine sent an emergency alert that read: "Active shooter situation at Ben Taub Hospital.  Do not go to Ben Taub Hospital.  If at Ben Taub, follow emergency response guidelines of the hospital.  More details as they become available."

Ben Taub Hospital confirmed that police are on-scene to investigate reports of an active shooter situation, according to KTRK-TV. More than 200 police officers arrived on scene, some armed with assault rifles.

A live feed can been seen here.

No injuries have been reported.

This story is developing and more details will be added as they emerge.

Houston Police Chief Art Acevedo has confirmed they have conducted a preliminary search of the building and have found no evidence of a shooter. SWAT will be conducting a secondary search. The alleged suspect has been described as a bald white man of an unknown age.

After a secondary SWAT search and K9 unit sweep of the building has come up empty, normal operations have resumed at the hospital. Police say they will review security cameras to investigate the details of the situation.