
An ex-student has been arrested in connection with the on-campus killing of a University of Arizona professor Wednesday.
Professor Thomas Meixner, who was the head of the hydrology and atmospheric sciences department, was shot and killed around 2 p.m. Wednesday at the school’s Tucson campus, according to the University of Arizona Police Department.
The shooting occurred in the school’s John W. Harshbarger Building, added the UAPD.
“It’s a tremendously tragic event. We feel so incredibly bad for the professor’s family, friends and colleagues, and our hearts really just go out to them,” University Police Chief Paula Balafas said during apress conferenceshortly afterward.
Moments before the shooting, a staff member alerted the UAPD to the presence of a former student who had entered the building without permission, Balafas added.
The staffer requested that police escort the ex-student off the premises, but tragically the UAPD’s officers were unable to reach the John W. Harshbarger Building in time to stop the shooting, during which a handgun was found to have been used, the police chief shared.
University of Arizona

After the shooting, the gunman reportedly ran from the building. Officers from the Arizona Department of Public Safety later apprehended former University of Arizona student Murad Dervish, 46, at a traffic stop outside the town of Gila Bend at 5:10 p.m, some 120 miles from the murder scene.
Dervish booked in the Pima County Jail at 6:20 p.m., Sgt. Sean Shields of the UAPD told PEOPLE. He was charged with murder in the first degree, pre-meditated, and aggravated assault with a deadly weapon.
Balafas shared that the UAPD currently does not know of a motive for the shooting.
The University of Arizona canceled all its classes following the tragic event and instructed students to either go home or return to their dorm rooms. Counseling services were also made available to students, per the school.
Arizona Police Department Instagram

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“I am incomplete shock,” wrote coworker Dr. Laura Meredith. “We just submitted a grant last week. I can’t think of a nicer or more supportive colleague/mentor/human. This is devastating and senseless. How sorry I am for so many people now in pain.”
source: people.com