Authorities don't know where the University of Georgia professor fled after he shot and killed his wife and two men in Athens on Saturday, or even if he still is alive.
But the "America's Most Wanted" television show added Zinkhan to a list of fugitives on its Web site Wednesday, and the program might produce a segment about the slayings.
"It's a nationally televised program that is watched by a lot of people, and hopefully people will see it and give us some insight" about where to find Zinkhan's trail, said Athens-Clarke police Capt. Clarence Holeman.
"We feel this will help us out a great deal," Holeman said.
Zinkhan vanished Saturday afternoon, after police say he opened fire with two handguns in broad daylight, killing his wife, Marie Bruce, 47, and two men, Tom Tanner, 40, and Ben Teague, 63, at a reunion picnic of the Town & Gown Players theater troupe at the Athens Community Theater on Grady Avenue.
"America's Most Wanted" has been pre-empted for two weeks, but when it next airs May 16, it might broadcast Zinkhan's photograph and other information, then do a longer segment later, according to one of the show's correspondents, Angeline Hartmann.
Investigators Wednesday also released a photograph of Zinkhan taken in February and showing him as he looked Saturday.
Local police had a hard time keeping up with a flood of tips that came in the first few days after the murders, but calls have trickled to a stop, Holeman said.
Authorities also don't have a motive for why Zinkhan may have shot the three people.
Police have said that Zinkhan argued with Bruce, and Teague tried to calm things down, but Zinkhan went to his SUV, returned with two handguns and shot the victims.
He drove to his neighborhood on Chesterton Drive in Bogart, where he dropped off his 10-year-old daughter and 8-year-old son with a neighbor and drove off. He and his SUV, a 2005 red Jeep Liberty with Georgia tag AIX1376, haven't been seen since.
The FBI took out a federal arrest warrant and agents are looking for him in several states where he has extended family.
A team of about a dozen agents from seven states are on the case, interviewing the fugitive's friends, relatives and acquaintances, according to Gregory Jones, special agent in charge of the FBI's Atlanta Division.
"We have wrapped our arms around a number of people who know him," trying to figure out where Zinkhan might have gone, Jones said.
From interviews with people who know Zinkhan, investigators have pieced together the picture of an intelligent but volatile person, who obviously is capable of murder, according to Jones.
"The fact that he has demonstrated his propensity to kill tells us he is to be considered armed and dangerous and we need to get him captured as soon as possible," the agent said.
Investigators don't know if Zinkhan is hiding or, as in many domestic violence murders, committed suicide.
"It goes without saying, anybody involved in such a horrendous act is unpredictable and you really hope it ends with the ultimate goal of finding him and bringing him to justice," Jones said. "But ultimately, he is the one who decides his fate."
Authorities believe Zinkhan might have disappeared into the forest along the Appalachian Trail because he liked to hike there. They alerted the state Department of Natural Resources, the U.S. Park Service and the Appalachian Trail Conservancy, the nonprofit that administers the trail under an agreement with the park service.
The trail conservancy posted a lookout for Zinkhan on its Web site, but park service rangers aren't actively searching for him, according to Ranger Eric Barron.
"At this point, we are assisting the agencies in Georgia by just getting the information out to hikers and all the law enforcement agencies along the trail," Barron said.
Anyone with information about Zinkhan should call police at (706) 613-3345. Anonymous calls may be placed with Crime Stoppers, at (706) 613-3342.
Barron may be contacted at the park service at (301) 639-0167.
Services for Bruce are planned for 11 a.m. today at Warren Baptist Church in Augusta, followed by burial in Westover Memorial Park.
A memorial service for Teague is scheduled for 11 a.m. Friday in the UGA Chapel on North Campus, followed by a public reception on Herty Field nearby.
Bernstein Funeral Home is handling arrangements for Tanner, but his family wants details kept private.