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Authorities say they are struggling to find the motive behind a University of Georgia professor's alleged slayings of his wife and two men. Answers are proving as elusive as the missing professor.

Law enforcement agencies nationwide are looking for marketing professor George M. Zinkhan, who was last seen dropping off his two children with a friend shortly after Saturday's shootings.

Athens-Clarke County Police Capt. Clarence Holeman said Monday that interviews with witnesses have yet to yield a motive. Family members were still baffled by the allegations.

"If they were having any type of problems, the family knew nothing about it," said Daisy Phelps, who says she was an aunt of Marie Bruce, who was Zinkhan's wife. She said Zinkhan, Bruce and their two children had just celebrated Easter with the family.

"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, breaking into tears. "All we know is my niece is dead."

Warren French, a UGA professor of business ethics who is Zinkhan's longtime friend, said Zinkhan never lost his temper during the six years when he held a stressful post as head of the school's marketing department.

"This is so out of character for him; first of all to get mad and second to ever resort to violence of any type," said French.

The manhunt for Zinkhan shifted away from this campus town Monday as the FBI revealed he had a plane ticket for the Netherlands later this week and left behind an empty passport wallet. A colleague said Zinkhan recently bought a phone that could be used overseas.

Police searched a thicket of trees for Zinkhan in this northeast Georgia county on Monday, but Holeman said the marketing professor is likely long gone.

"Would you be sticking around if you had three murder warrants?" Holeman asked. "We don't think he's still around. He's probably trying to get as far away from us as he possibly can."

Relatives are cooperating with authorities to find Zinkhan, his brother told The Associated Press.

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

Gunfire erupted midday Saturday at a gathering of a local theater group at the Athens Community Theater. Killed were Bruce, a 47-year-old attorney, 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.

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 (110 kilometers) 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.

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.

French, the business ethics professor, 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.

He said Zinkhan rarely talked about his wife, who he met while working at UGA, though he spoke adoringly of their two children.

"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. Holeman said they were in the custody of Bruce's brother.

"I have these children in my house and that's all I can think about now," said 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.

Holeman said local investigators' hands were tied if Zinkhan has left the county's borders.

"We put a lookout in all 50 states and that's all we can do," he said. "We just put the word out — that's all we can do."

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