With Walls’ Execution, Northwest Florida Confronts Its Serial Killer Past

In Brief:

Frank Walls, Okaloosa County’s most notorious serial killer, is scheduled for execution today.
Mark Riebe operated in Northwest Florida from the late 1970s through the early 1990s, suspected of over a dozen murders.
Other notable violent crime cases in the region include Edward Zakrzewski II, Aileen Wuornos, and Danny Rolling.

Okaloosa & Walton Counties, FL – As Florida prepares to execute Frank Athen Walls on December 18, 2025, the region reflects on the history of serial killers in Northwest Florida.

Since 1980, law enforcement and historical records have identified two serial killers as the most prominent in Okaloosa and Walton counties.

Frank Athen Walls is widely recognized as Okaloosa County’s most notorious serial killer. Active between 1985 and 1987, Walls was convicted and admitted to five murders, including the 1987 slayings of Ann Peterson and Edward Alger in their Ocean City mobile home. After decades on death row, his execution is set for today.

Mark Riebe is often mentioned alongside Walls. Operating in the Northwest Florida Panhandle from the late 1970s through the early 1990s, Riebe was formally convicted for the 1989 murder of Donna Callahan in Gulf Breeze. He has confessed to, and is suspected of, over a dozen additional murders across the region, including cases in Okaloosa County. Many of these confessions remain unverified, but his activity has left a lasting mark on the region’s criminal history.

While Walls and Riebe represent the area’s known serial killer cases, other high-profile violent crimes have impacted the community:

Edward James Zakrzewski II, who committed a mass murder of his wife and two children in Mary Esther (Okaloosa County) in 1994. Zakrzewski was scheduled for execution in July 2025.
Aileen Wuornos, whose early criminal activity included minor offenses in Northwest Florida, carried out her infamous serial killings (1989–1990) primarily in Central Florida.
Danny Rolling, the “Gainesville Ripper,” committed a string of murders in 1990, targeting victims in Alachua County.

“The history of violent crime in Northwest Florida serves as a sobering reminder of the challenges law enforcement and communities face in protecting residents,” said a local law enforcement spokesperson. “The execution of Frank Walls marks the closing of a chapter on one of the area’s most notorious criminals, but the region remains vigilant in addressing violent crime and supporting victims.”

As Walls faces execution today, the legacies of both Walls and Riebe remain part of the ongoing discussion around criminal justice, prevention, and awareness in Northwest Florida.