Raleigh, N.C. — More than three months after her death, a 14-foot-by-48-foot billboard asking the question "Who Killed Jennifer Nielsen?" was unveiled Tuesday in an effort to draw new attention to a Fuquay-Varina mother's unsolved slaying.

Eight months pregnant at her death, Nielsen, 22, known as Jenna, was delivering USA Today newspapers in the early morning hours of June 14 when she was attacked and stabbed to death. Her body was found behind the AmeriKing Food Mart on Lake Wheeler Road in Raleigh.

The billboard, donated by Fairway Outdoor Advertising, sits at 3525 S. Wilmington St., faces north and features a large police composite of a person of interest, a photo of Nielsen and a toll-free tip line to the national TV show "America's Most Wanted," which also partnered with Nielsen's family.

Nielsen's husband, Tim Nielsen, called the billboard "outstanding and overwhelming" and said he believes the key to finding his wife's killer is keeping the case alive.

"Now that this billboard is up, it's 24/7, and we think this is the key, right here, to getting this person off the streets," he said.

Approximately 46,460 vehicles travel by the billboard, located about three miles from the crime scene, every day, a Fairway representative said. It will likely stay there for the next few weeks before the company moves it to another location.

Fairway said it would determine future spaces based on availability but that they planned to keep it up near the crime scene as much as possible until police make an arrest.

The case has drawn national attention, with Tim Nielsen appearing on network news shows such as Fox News' "On the Record." "America's Most Wanted" has featured the case at least twice, and USA Today has published several full-page advertisements seeking tips.

Maj. Ken Mathias, of the Raleigh Police Department, said Tuesday that the police department has received about 1,000 calls, in addition to e-mails and letters, and said the family has been "an important component" in their investigation.

"The family, in this case, has been instrumental in helping us, partnering with us, to keep this in the media," Mathias said.

Still, police have yet to name a suspect.

The person of interest, according to Raleigh police, is a man believed to be in his late teens or early 20s, standing about 5 feet, 3 inches tall and weighing about 120 pounds. He had black hair pulled into a ponytail and wore a dark-colored sleeveless shirt and baggy denim shorts. Police believe he might be Hispanic.

Anyone with information about the case should call the Raleigh Police Department's tip line at 919-227-6220 or "America's Most Wanted" tip line at 1-800-CRIME-TV. They can also report a tip via the NC Wanted tip line at 1-866-43-WANTED or submit it over the Web.

Nielsen's family has set up a Web site, justice4jenna.org, in an effort to keep the case alive and is offering a $10,000 reward for information leading to a conviction in the case.

Nielsen's father, Kevin Blaine, said Tuesday that the power of the Internet has helped keep the case in the public eye. The Web site has had more than 39,000 hits from visitors as far away as Australia and Asia.

"We want to catch the person that did this. And the only way we know how is to help generate tips for the police – to make it easier for them," Blaine said. "I don't want this to go on for years and years. I want this done, right now."