Vikings running back Onterrio Smith was detained last month at Minneapolis-St. Paul Airport after police found paraphernalia later identified as a kit used to circumvent drug tests.

Smith was neither arrested nor charged, but as of Tuesday it was unclear whether the incident will affect his status in the NFL's confidential substance-abuse program.

Smith acknowledged to airport police that he was carrying dried urine, along with a device called "The Original Whizzinator" and a bottle of pills labeled "Cleansing Formula." He told police the kit was "for making a clean urine test," according to the police report, and said he was taking the materials to his cousin.

Smith was suspended four games last season after testing positive for marijuana, his second "strike" in the league's program. A third "strike" would result in a yearlong suspension. An attempt to substitute a urine specimen qualifies as a positive test, but NFL spokesman Greg Aiello did not immediately know Tuesday whether possession of a masking device fits that criteria.

Smith could not be reached for comment. His agents -- Michael Sullivan, Doug Hendrickson and Jeff Sperbeck -- declined to comment. Vikings coach Mike Tice said he was unaware of the incident and had no comment.

According to the police report, a bag Smith was carrying set off security alarms before an April 21 flight. The alarms later were traced to a tube of toothpaste.

During the search, a Transportation Security Administration officer found "six or seven" vials of white powder in a clear bag, according to the report. Airport police were called to the scene and began inspecting the materials in a private room.

A sample from one of the vials tested negative for cocaine and opiates. Smith was then led into the room and identified the powder as dried urine. He also acknowledged the presence of a Whizzinator.

Smith was allowed to leave after questioning.

The $150 device includes a prosthetic penis attached to a jockstrap and plastic bag. Using a syringe, the user fills the bag with a precisely measured amount of water blended with the urine powder to create a clean sample. When the user takes a drug test in front of an observer, the water is released through the prosthetic with a valve (the instructions recommend the user cough to hide the sound of the valve unsnapping).

On its website, manufacturers of The Original Whizzinator market the instrument as an "undetectable,"foolproof" and "re-usable" urinating device.

Like other professional sports leagues, the NFL administers random drug tests to players.

According to Aiello, the NFL's testing guidelines include having the player take his shirt off and pull his pants down below his knees in front of an observer.

Smith, 24, was kicked off the University of Tennessee football team in 2000 for marijuana use and finished his college career at Oregon. Scouts considered him one of the top running backs available in the 2003 draft, but questions about his past drug use and character dropped him to the fourth round.

He rushed for 579 yards as a rookie and led the Vikings last season with 544 yards. Barring another suspension, Smith is expected to compete with Michael Bennett and Mewelde Moore for the starting job.