A builder found on the roof of a Hatton Garden business was beaten to death in a "vicious" attack, police said.
Officers initially thought the man had fallen from a height when they were called to the commercial property in Clerkenwell at 14:41 BST on Tuesday - writes bbc.com
A 24-year-old man has now been arrested on suspicion of murder and police are looking for a second man.
The 47-year-old victim had been working at the site. His next of kin has been informed.
The other suspect seen fleeing the scene is white, in his mid 20s, and was wearing a navy fleece jacket, blue jeans and brown workmen's boots.
DCI Luke Marks said: "It is believed that the victim was viciously attacked by an unknown suspect."
Read more news of London on our site.