April 24, 2024

HARRISON COUNTY, Iowa - The victim in the April 21, 2024 Harrison County homicide has been identified as 53-year-old Douglas Lynn Manley of Missouri Valley, Iowa.

The Iowa Office of the State Medical Examiner has ruled Manley’s death as a homicide caused by blunt force trauma.

Sebastin O’Brien remains in the Harrison County Jail on no bond and has a preliminary hearing scheduled for May 1, 2024. Note: A criminal charge is merely an accusation and a defendant is presumed innocent until proven guilty.   


April 22, 2024

HARRISON COUNTY, Iowa - At approximately 4:30 p.m. on April 21, 2024, the Harrison County Sheriff’s Office responded to a call of a vehicle rollover south of Modale, Iowa. When deputies arrived on scene, they contacted the driver of the rollover, identified as 22-year-old Sebastin O’Brien of Little Sioux, Iowa. O’Brien became combative with deputies, and after a short struggle, deputies placed O’Brien into custody.

Upon further investigation, it was learned the rollover vehicle did not belong to O’Brien. Harrison County deputies went to the residence of the vehicle’s registered owner and located the owner deceased inside the residence. The name of the deceased individual is being withheld pending notifications to family members.

As a result of evidence collected, O’Brien was charged with Murder in the 1st Degree and taken to the Harrison County Jail. Additional charges are pending.

The criminal investigation is being conducted by the Harrison County Sheriff’s Office with assistance from the Iowa Division of Criminal Investigation and Iowa State Patrol. The deceased male was transported to the Iowa Office of the State Medical Examiner in Ankeny where a forensic autopsy will be performed this week. 

The investigation is ongoing, and no other information will be released at this time. Note: A criminal charge is merely an accusation, and a defendant is presumed innocent until proven guilty.


The Iowa Department of Public Safety (DPS) is the largest law enforcement agency in the state. It includes seven divisions and several bureaus, all working together with local, state, and federal government agencies and the private sector to keep Iowa a safe place by following our core values: leadership, integrity, professionalism, courtesy, service, and protection. Divisions within the Iowa DPS: Iowa Division of Criminal Investigation, Iowa Division of Narcotics Enforcement, Iowa State Patrol, Iowa State Fire Marshal Division, Iowa Division of Intelligence and Fusion Center, Professional Development and Support Services Division, and Administrative Services Division. The Department of Public Safety is led by the Commissioner who is appointed by the Governor.

Iowa Department of Public Safety

215 E. 7th St.

Des Moines, IA 50319