BERKELEY -- Family members of Maria Jane Weidhofer announced Wednesday that they hope a $10,000 reward would prompt witnesses to come forward and solve her murder in Tilden Regional Park in the Berkeley hills nearly 15 years ago.

East Bay Regional Park District police and the Carole Sund/Carrington Memorial Reward Foundation are contributing $5,000 each to reward information leading to the arrest and conviction of those responsible for the 32-year-old Oakland woman's death in November of 1990.

Flanked by her two sons and a daughter-in-law at a news conference in Tilden Park, Weidhofer's mother, Jane Weidhofer, who now lives in Amador County, said, "My family and I wish to express our thanks" for the reward.

Weidhofer said, "We've had to live with the loss of our daughter and sister every day for nearly 15 years. We hope this tragedy will not happen to another family."

Weidhofer, 32, a native of Claremont, Calif., who graduated from the University of California, Davis, with honors in studio art and worked for a macriobiotic bakery in Emeryville, regularly jogged on the Nimitz Way Trail, which is adjacent to the scenic Inspiration Way parking lot and is a site popular with runners, walkers and bicyclists.

But Weidhofer didn't return home after she went jogging the afternoon of Nov. 15, 1990.

About 7 p.m., a neighbor told police that Weidhofer hadn't returned home, so East Bay Regional Park District police checked Inspiration Point and found her blue Toyota pickup truck in the parking lot. Her purse was found undisturbed inside the truck.

Police searched for Weidhofer throughout the night and found her body in the early morning hours of Nov. 16, 1990, in Redwood Grove, just off of the Nimitz Way Trail, about one mile north of Inspiration Point.

A pathologist determined that Weidhofer died from strangulation and that she had been sexually assaulted.

The perpetrator "must be depraved," Jane Weidhofer said.

Park District Detective Sgt. Dale Davidson said police are hopeful that the reward will prompt someone to come forward and provide information that will help police solve the case.

Davidson said that although many people were interviewed by investigators shortly after the crime, no suspect ever was identified.

"The leads we followed we took to their logical ends and we can't go any further with them," Davidson said.

DNA evidence in the case remains on file with the California Department of Justice, he said.

Jane Weidhofer said her daughter inherited artistic talent from her father, Karl Weidhofer, a successful oil painter who died four years ago.

Jane Weidhofer said her daughter was considering going into textile design at the time she was murdered.

Because Maria Weidhofer was killed, "she was deprived of her artistic talents and the chance to be a mother and a grandmother," Jane Weidhofer said.

Hans Weidhofer, a computer technician who lives in Angels Camp, described his sister as "a free spirit."

Rolf Weidhofer, a general contractor in Chico, Maria's Weidhofer's other brother, also attended the news conference.

People with information on the incident may call the Weidhofer Information Hotline at (510) 544-3129 or Detective Sgt. Dale Davidson at (510) 544-3104.