WICHITA, Kan. —  A package of items believed tied to the BTK serial killings (search) was found Tuesday in a Wichita park, police said.

A resident found the package — wrapped in plastic and held together by a rubber band — then contacted local television station KAKE-TV. The station subsequently called police.

Wichita police officials released a statement saying they had submitted the contents of the package to the FBI (search) for authentication.

The BTK serial killer, whose nickname stands for "Bind, Torture, Kill," is linked to eight unsolved murders from 1974 to 1986. He resurfaced in March with letters to media and police.

KAKE-TV showed film footage of the contents of a package, including an unidentified wrapped metallic object and blurred images of three pages purported to be a list of chapters of a book entitled "The BTK Story."

The station reported the package contained what appears to be the actual driver's license of Nancy Fox, (search) who was found tied up and strangled in her home on Dec. 8, 1977. BTK's voice was captured on tape when he called a dispatcher to report Fox's murder.

In a 1978 letter, the killer also included a poem titled "Oh! Death to Nancy" that had striking similarities with the lyrics of the old folk song "Oh Death."

Police said they have received close to 5,000 tips from the public since BTK resurfaced in March.