The manhunt for a University of Georgia professor suspected in the shooting deaths of his wife and two men shifted away from this campus town Monday as the FBI revealed he has a plane ticket for the Netherlands later this week and left behind an empty passport wallet.

George M. Zinkhan has not been seen since the shootings near campus Saturday, and law enforcement agencies nationwide have been enlisted in the search for the marketing professor, authorities said. His relatives also have been working to help Athens-Clarke County police and the FBI to find him, his brother told The Associated Press.

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"We are doing all we can to prevent any additional violence," Chris Zinkhan said in an e-mail.

Gunfire erupted at a midday gathering of a local theater group at the Athens Community Theater. Killed were George Zinkhan's wife, 47-year-old attorney Marie Bruce, and two members of her theater group, Ben Teague, 63, and Tom Tanner, 40. Zinkhan, 57, disappeared after the shootings in a red Jeep Liberty. Authorities say they don't know what motivated the shootings.

As classes resumed Monday on the campus where Zinkhan had taught since the 1990s, the university announced that the marketing professor had been fired. As a precaution, university police carried assault rifles as they patrolled on foot, but University Police Chief Jimmy Williamson said investigators believe Zinkhan had left Athens, 70 miles east of Atlanta.

"We feel that he is no longer local," Williamson told reporters, though he declined to say why. "We just don't think he is close by."

Still, the university's president urged everyone to use caution until Zinkhan is found.

A breathless man called 911 to report the shootings to Athens police, according to a recording of the call posted on The Atlanta Journal-Constitution's Web site.

"He shot three people, two gunshots to one man," the caller told the dispatcher who asked for a description, which was provided by another witness.

"Tall white male, 50s, goatee beard, I think, wearing blue shorts, like a T-shirt." The witness told police the man was heading away from town.

Calls by AP to police to obtain the recordings had not been returned.

Delta Air Lines confirmed Zinkhan has a ticket to Amsterdam for May 2, FBI Special Agent Gregory McClendon said in a federal court affidavit as part of a criminal complaint accusing Zinkhan of flight to avoid prosecution. McClendon said Zinkhan might change the date and try to leave early. The documents also include a request for a warrant to arrest Zinkhan and it was signed by a federal magistrate judge.

The affidavit did not say when the ticket was bought, although a family friend told investigators that Zinkhan's wife had said Zinkhan had scheduled a trip to Amsterdam. A colleague of Zinkhan's told authorities the professor had recently purchased a phone that could be used internationally.

Warren French, a UGA professor of business ethics and Zinkhan's longtime friend, said Zinkhan has traveled to Amsterdam twice a year — at Christmas and during summer break — for the last two years. He has taught part-time at the Vrije Universiteit (Free University) since April 2007.

French said Zinkhan had a voracious intellect, often getting little sleep because he would read through the night. French said Zinkhan succeeded him as head of the school's marketing department in 1994, and held the job for six years. While passionate about his work, Zinkhan never seemed controlled by his emotions, he said.

"As department head, he caught the flak you normally get from faculty members and students. He never lost his temper. He just seemed to take it," French said. "This is so out of character — for him first of all to get mad and second to ever resort to violence of any type."

It was after he became department head that Zinkhan met Bruce, who worked there as a student adviser and communications director before she went to law school, French said.

He said Zinkhan rarely talked about his wife, though he spoke adoringly of their two children. Zinkhan threw a party at their house for Bruce's 40th birthday several years ago, and French said he had dinner at the couple's home last year.

"They are both free spirits, and as free spirits, they seemed to be happy," French said.

Police said, after the shooting, Zinkhan dropped his two children, ages 8 and 10, with a neighbor. Athens-Clarke County Police Capt. Clarence Holeman said are the custody of Bruce's brother.

"I have these children in my house and that's all I can think about now," a woman who answered the phone at that brother's house Monday who identified herself as his wife. She said the family had no further comment.

Bruce's mother, Betty, declined comment when reached by telephone at her home in Augusta. Daisy Phelps, who identified herself as Bruce's aunt and Betty Bruce's sister, said Zinkhan, Bruce and their children had just celebrated Easter with the family.

"If they were having any type of problems, the family knew nothing about it," Phelps said.

Phelps said Bruce's friends in Athens also told the family they were not aware of any problems between the couple.

"We're all torn up about this. It's awfully hard to talk about it because we just don't understand. We don't know why. We don't know," Phelps said, crying. "All we know is my niece is dead."

The shooting victims were members of the Town & Gown Players, which was staging a performance of "Sherlock Holmes: The Final Adventure" at the theater. A few dozen members of the group were gathered for a reunion Saturday at the time of the shooting. Two others were hurt by bullet fragments.

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