Police were called to reports of a man with a knife in Mitcham yesterday - but no one was found.
The reports were made just before 3.35pm in Gaston Road.
Police searched the area but couldn't find the man - although they do think they know the man's identity.
Officers are conducting further enquiries but there have been no arrests at this time.
There were no reports of any injuries.
A Metropolitan Police spokesperson said: "Police were called at 15:34hrs on 14 September to Gaston Road, Mitcham after a man was reported to be in possession of a knife.
"Officers responded and conducted an area search but the man was not found.
"Police believe they know the man's identity and are conducting further enquiries.
"There have been no arrests at this time.
"There were no reports of any injuries."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here