Harry Styles was left "shaken up" after he was mugged at knifepoint during a night out on Valentine's Day.
The Sun report the former One Direction singer was confronted by a man demanding cash in North London last Friday.
The 26-year-old is said to have handed over his money and was not harmed in the robbery.
"He actually played it pretty cool, quickly giving the assailant cash, keeping himself and the guy calm and getting the situation over with," a source told the Mirror.
"Understandably though it left him very shaken up afterwards."
A Metropolitan Police spokesperson told the Mirror: "Police are investigating reports of a knifepoint robbery.
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"Officers were contacted on Saturday, 15 February regarding the incident which happened at 23.50hrs on Friday, 14 February.
"It was reported that a man in his 20s was approached by another man and threatened him with a knife.
"The victim was not injured however, cash was taken from him.
"No arrests and inquiries are ongoing."
Styles is set to appear at the Brit Awards today where he will perform following the December release of his solo album Fine Line.
He is in the running for two awards after being nominated for Best British Album and Best British Male Solo Artist.
Styles' mugging comes after a stalker, Pablo Tarazaga-Orero, was found guilty of harassing him near his home.
The offender was served a restraining order banning him from being within 250 meters of the pop star and going to any of Styles' concerts.