The 42-year-old funny man was mugged by two men who approached his stationary Range Rover on mopeds.
Michael’s publicist told the BBC the comedian was “fine” following the incident in west London.
The Metropolitan Police said in a statement to the website that they were called at 1.39pm to reports of a robbery.
“The victim was stationary in his car when two males on a moped smashed the car windows with a hammer before stealing property,” the statement read.
No injuries were reported and no arrests have been made, they said.
The police also urged anyone with information to come forward, adding: “Inquiries continue.”
The star is believed to have been sitting in the car alone when the incident happened.
The muggers attacked the window of his Range Rover with a hammer before demanding Michael handed over his watch, thought to be worth around £5,000, it’s reported in The Mirror.
In pictures obtained by The Sun, the window of the driver’s seat could be seen smashed.
A witness, who did not want to be identified, told the publication: “I was driving along the road when I saw two men dressed head to toe in black.
“One man was on the bike and the other was either attacking or fighting Michael McIntyre. There was shouting too.”
The woman continued: “The driver’s window of his Range Rover was completely smashed.
“The second guy jumped on the back of the motorbike and they got away.”
Meanwhile, MailOnline reported that another witness said: “The guy at the front of the moped started to hit the driver’s window about ten to 15 times and it eventually just cracked.
“He opens the door and gets Michael McIntyre out of the car. Michael fell but he was still trying to put up a fight.
“I just remember one of the bikers trying to get something. I don’t know what the guy was trying to get – a watch, a wallet, maybe?”
The father-of-two is said to have unfastened the strap and handed over the watch.
According to reports, the thieves swiftly left the scene.
Express.co.uk has contacted a representative for Michael McIntyre asking for comment.
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