The exact nature of the incident is not yet known.
A woman has been taken to hospital after an attack at a shop on Chapel Street.
A man has been detained at the scene.
A number of police vans and ambulances are on Chapel Street in the town centre and a police cordon is on place around TUI travel agents.
Merseyside Police said in a statement: “Merseyside Police can confirm officers are currently at the scene of an incident in Southport.
“Officers were contacted at 1.25pm today, Saturday 13th January, following reports of concern for a female at a shop on Chapel Street.
“A female has been taken to hospital. A male has been detained are the scene.
“The incident remains ongoing.”
Photos taken at the scene show the police cordon covering a large section of Chapel Street around the TUI travel agents.
More to follow.