Philadelphia homicide detectives are continuing their investigation. Use of deadly force will be investigated by university authorities and the District Attorney's Office.
The campus has its own Division of Public Safety, with 116 police officers, and contracts 450 privately employed security officers. There are also 85 surveillance cameras on campus.
Campus police, some of whom are retired from the city's force, must graduate from a state-certified academy. Rush said Penn's officers were a mix of veterans from different departments and included officers from Montgomery and Delaware Counties.
Every year, officers are required to take an eight-hour refresher course, including a shooting qualifier, Rush said.
She said it was unusual to have a single fatal shooting by campus police in any given year, let alone two.
"The difference this year is people are willing to shoot at police," Rush said.
Late last month, KoKo Bongo, a nightclub in the same building complex as Wizzards, was shut down after a fight erupted while a huge crowd was leaving the bar.
Police were heavily concentrated because of a confrontation there a week earlier; nonetheless, a 21-year-old gunman was killed after exchanging shots with city police. A city officer and a bystander were also wounded by gunshots.
University officials expressed concern about both incidents and yesterday afternoon sent an e-mail to students and employees informing them of a "serious incident that occurred on the periphery" of campus.
"The university has pursued every available means to prevent these types of incidents from occurring in the future, including additional police overtime, extra patrols, additional lighting and surveillance cameras," the e-mail said.
The note also said university officials would continue to meet with city officials to curtail violence associated with local bars. Although KoKo's was shut down by the city last month, it reopened this weekend.
A woman who answered the phone at Wizzards yesterday said no one was available for comment.
Hours after the Wizzards' shooting, officials from the city's Department of Licenses and Inspections posted a "Cease to Operate" order, closing the club until a hearing could determine otherwise.
"We're very grateful to hear that, quite frankly," Rush said of the order to close the club.
Inquirer staff writer Thomas Fitzgerald contributed to this report.