(CNN) -- A former University of Georgia professor, wanted in the fatal shootings of his wife and two other people over the weekend, purchased a plane ticket to the Netherlands for May 2, authorities said Monday.
An alert on the UGA Web site says professor George Zinkhan is a suspect in an off-campus shooting.
A nationwide manhunt for George Zinkhan, 57, extended into a third day with no sign of him, authorities said.
Zinkhan was a marketing professor at the university's Terry College of Business, but was terminated on Sunday, the day after the shootings, university officials said.
Zinkhan had previously purchased the plane ticket to the Netherlands, said Gregory Jones, special agent in charge for the FBI's Atlanta, Georgia, office. Authorities say Zinkhan owns a home in Amsterdam, Netherlands.
The FBI is working with its agents overseas and police in the Netherlands, Jones said.
A nationwide alert for Zinkhan has been issued by Athens-Clarke County police.
The shootings took place at a community theater group's reunion Saturday in Athens, Georgia, just off campus.
Police Capt. Clarence Holeman identified the victims as Marie Bruce, 47, Zinkhan's wife and a prominent Athens attorney; Tom Tanner, 40; and Ben Teague, 63.
The university terminated Zinkhan on Sunday, President Michael Adams told reporters on Monday.
Police said Zinkhan has relatives in Texas and owns a home in Amsterdam, Netherlands. He was last seen driving a red, 2005 Jeep Liberty after the shootings Saturday.
Authorities do not believe Zinkhan is still on campus or in the city of Athens, University Police Chief Jimmy Williams said Monday. As a precaution, he added, security has been beefed up on campus, including officers on foot patrols carrying semiautomatic weapons.
The victims were all associated with the Town and Gown Players, a theater group that was holding a reunion picnic at the time of the shootings.
"The three people we lost (Saturday) were a part of the rich 50-year history of this theater and, more than that, were vital members of the Town and Gown family," the organization said Sunday on its Web site.
The site described Bruce as "the binding force that held the Town and Gown community together."
"Having worked with Town and Gown for over 20 years, at one time or another she served in every capacity at the theater, artistically and administratively, from leading lady to president of the board to chief cook and bottle washer."
Holeman said Saturday, "It appeared (Zinkhan) and his wife (Bruce) were having problems."
Meanwhile, the university said that classes would be held Monday, as the school term enters its final week.
In a letter "to the members of the University of Georgia community" posted on the school's Web site, Adams said operations would continue uninterrupted. But, "I urge everyone to continue to exercise caution until the suspect is apprehended," Adams said.
Adams' letter said counseling would be available to any member of the faculty or staff and to students.
The university's annual end-of-year campus memorial service, in which those lost over the past year are remembered, is scheduled for Tuesday night, Adams said. Victims of Saturday's shooting will be honored at that service.
Police said Zinkhan was not at the Town and Gown event originally but arrived and, according to Holeman of the Athens police, got into "a disagreement" with his wife. He left the scene, and police believe he went to his car, where the couple's children apparently were waiting, and returned with two handguns.
The shootings "only took a few minutes," Holeman said. Police found eight shell casings.
After the shooting, Zinkhan left the scene with his children -- ages 8 and 10 -- still in the vehicle, police said. He drove to a neighbor's home in nearby Bogart, Georgia, where he lived and left the children there.
The neighbor, Bob Covington, told CNN that Zinkhan arrived at his home shortly after noon with the two children.
"He rang the doorbell, asked me if I could keep his kids for about an hour," Covington said. "I said sure, and he said there'd been some type of emergency, and he took off."
Zinkhan seemed hurried and agitated but that seemed consistent with an emergency, Covington said. He didn't question Zinkhan about the emergency, Covington said, adding that it wasn't unusual for someone in his family to watch the children.
An hour or so later, he said, police arrived and took the children.
Police searched Zinkhan's home on Saturday, but there was no indication of what evidence they might have gathered there. University police were assisting Athens-Clarke County police in their investigation, officials said Monday.
The university activated its alert system following the shooting with a description of the suspect, said spokesman Tom Jackson.
Statistics show the university was able to reach 82 percent of the 64,000 people it attempted to contact, he said, adding that some of the calls went to university offices unstaffed on weekends. An alert was also posted on the school's Web site, and an all-campus e-mail was sent Saturday night.
Adams said the university's provost and deans would determine how to handle the remainder of classes and exams for the classes -- one graduate and one undergraduate -- taught by Zinkhan.