Two people died and seven are being treated for injuries after a shooting Thursday afternoon inside the University of Pittsburgh Medical Center's Western Psychiatric Institute and Clinic, the center said on Twitter, citing police.
In a post a few minutes later, the medical center said police had indicated that one of the two "confirmed dead ... is believed to be the shooter."
Earlier Thursday afternoon, the University of Pittsburgh reported on its own Twitter account that an "active shooter has been identified at Western Psychiatric Institute."
The same post said that there were "several injured."
About 30 minutes later, the same Twitter account posted that a "possible 2nd actor" was involved, and "lock-down (was) recommended until further notice."
But in a post about 4 p.m., the center said "there was no second shooter." It also said there was "no hostage situation," as had been reported elsewhere.
After initially citing "conflicting reports about casualties," the University of Pittsburgh Medical Center said that an unidentified number of injured were being treated in the UPMC Presbyterian hospital's emergency department.
"Measures have been put in place to secure hospital and keep patients/staff safe. We continue to work with police," the medical center said via Twitter.
The larger University of Pittsburgh, meanwhile, had by then suspended its shuttle system "in the O'Hara Street (Mid Campus) area until further notice."
The University of Pittsburgh School of Medicine's psychiatric department is based at the institute, which describes itself on its website as a "leader in the treatment of mental health and addictive disorders."
U.S. News and World Report ranks University of Pittsburgh Medical Center -- thus, the Western Institute -- as being the nation's eighth best psychiatric hospital.