Wichita ? A Wichita television station turned over to police Wednesday a suspicious letter it believes may have come from a serial killer. But police cast doubt on its authenticity.

“There is really nothing to report on this,” Janet Johnson, spokeswoman for the Wichita Police Department told The Associated Press. “As you know we have received many, many suspicious letters. If we thought this was for real we would be holding a press conference.”

No press conference was immediately scheduled.

“We got a suspicious letter in the mail today (Wednesday),” said KAKE-TV marketing director Bryan Frye. “We turned it over to police as a suspicious letter and they have the evidence now.”

Frye said the letter was suspicious enough that the station thought it should let authorities decide whether it was authentic.

KAKE television reported the letter contained a puzzle and photocopies of employee identification cards for two men: a former Southwestern Bell worker and a former employee of the Wichita public school district.

The station did not identify either man, but said it talked to the former phone company employee just minutes after Wichita police detectives left his house. He told the station he was baffled and had no idea why his business card would have been in the letter.

The school district checked its records and found a similar name, but said the title of “special officer” cited in the letter did not exist, KAKE said.

The envelope used a nonexistent return address.

Authorities believe the serial killer — known as BTK, for “Bind, Torture, Kill” — killed at least seven people between 1974 and 1978. In March, BTK resurfaced when he sent a letter to The Wichita Eagle newspaper claiming responsibility for an eighth killing in 1986.

BTK has a history of taunting police with letters to news organizations. Letters claiming responsibility for the slayings, which remain unsolved, were sent to The Wichita Eagle and KAKE, the last coming in 1979 until the letter to the Eagle surfaced earlier this year.