Merseyside Police has arrested a 37-year-old woman on suspicion of murder following the discovery of a man's body in New Brighton.
Officers were called to Egremont Promenade at 5.50am after a member of the public found a man aged in his 40s lying in the street with a head injury.
Paramedics pronounced the man dead at scene.
The area where the man was found was cordoned off by police, who are examining the area for evidence.
Officers are looking at CCTV and going house-to-house, while a number of roads remain closed to the public.
The circumstances of the man's death are under investigation and a Home Office post mortem will be carried out later to establish a cause of death.
The woman remains in police custody at this time.
Anyone with information is asked to contact detectives in Wirral on 0151 777 2265 or call Crimestoppers on 0800 555 111.