A man is refusing to move after climbing into a gantry on the M1, causing police to close part of the motorway while they try to persuade him down.
The man, who has not been named but was dressed in a black hoodie, has also daubed messages in mud on the back of the sign, near junctions 22 and 23.
One appeared to say "CCTV miss 2 murder attempts" and another saying someone "tried 2 kill me".
The man also was seen angrily shouting and banging his hands against the gantry, according to the Leicester Mercury.
He has been there since climbing into it on Sunday afternoon.
Overnight police positioned spotlights on the man but he remained there on Monday.
Leicestershire Police said that officers were called to the scene in the parish of Copt Oak just after midday yesterday after concerns were raised for the welfare of the man.
Chief Superintendent David Sandall said: "We are working hard to resolve the situation but to ensure the safety of the man and the public it is necessary to keep the motorway closed.
"We have trained police officers communicating with the man in order to reach a safe conclusion but this may take some time. We will continue to keep the public updated and will of course reopen the road as soon as possible."
Diversions have been put in place by the Highways Agency but motorists are being advised to avoid the area as traffic is heavily congested.