Authorities in Washington are asking the public's help to find a missing woman who's feared to be the victim of foul play.

The Pierce County Sheriff's Office said in a news release Monday that Shantel Holznagel, 29, was reported missing earlier this month after several weeks during which her family didn't have contact with her.

The sheriff's office said that the last known communication from Holznagel was on Aug. 9, when "she reportedly messaged a friend that she needed help."

"Detectives have received information that there were rumors that Shantel Holznagel was assaulted by unknown person(s) at an unknown location," police said. "Detectives are concerned that Holznagel may have been a victim of foul play and are looking for any information on her whereabouts and the rumored assault."

Authorities are concerned that Shantel Holznagel may have been a victim of "foul play," and said she was last heard from in early August. (Pierce County Sheriff's Office.)

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Holznagel is described as 5-7, 150 pounds with brown hair and brown eyes. The 29-year-old has several tattoos, including the words "Angel face" on her back and an image of a diamond on her left ankle, according to police.

Crime Stoppers of Tacoma-Pierce County is offering a reward of $1,000 for information leading to an arrest and charges filed in the case. Anyone with information about Holznagel's whereabouts or the suspected assault is urged to contact the Pierce County Sheriff's Office or Crime Stoppers at 1-800-222-TIPS.