A man has been killed at a bus stop outside Britain's busiest rail station.
Police were called to reports that a man had been attacked near London's Waterloo station at around 2.45am.
Officers and London Ambulance Service found a man in his 40s with serious head injuries. He was pronounced dead at the scene.
A 29-year-old man was arrested nearby on suspicion of murder. He is in custody at a south London police station.
The victim has not yet been formally identified but police are in the process of informing next of kin.
Road closures and police cordons are in place around the scene of the killing, police said.
Detective Chief Inspector Diane Tudway, from the Homicide and Major Crime Command, said: "This is a very busy part of London frequented by both commuters and those on a night out. My team is keen to hear from anyone who was in the area or passing by at the time of this incident and may have witnessed what occurred or seen something that could assist the investigation.
"I would urge all witnesses and anyone with information to contact the incident room on 0208 721 4005 or call Crimestoppers anonymously on 0800 555 111."
Waterloo station saw 98.4 million entries and exits from passengers in 2013-14, according to figures from the Office of Rail Regulation.