"Kensington CID [Criminal Investigation Department] launched an investigation about an alleged assault on a 43-year-old man following an incident ... on the 24th of April at about 10 a.m.," a Metropolitan Police rep tells PEOPLE.
On Wednesday, the UK's Daily Star published photographs of Grant, 46, holding a plastic tub over his head and an article saying he lashed out at a paparazzo, leaving him "bruised, battered and covered in baked beans."
The police rep, who according to protocol cannot identify persons unless they are charged with a crime (it has yet to be decided whether Grant will be charged), told PEOPLE that on April 25, "At 7:30 p.m. a 46-year-old man was arrested in connection with the inquiry and taken to a central London police station. He has been bailed to return on a date in May pending further inquiries."
The incident allegedly began after photographers Ian Whittaker, 43, and Darren Goff, 37, spotted Grant arriving home in his Audi S4. Grant was dressed in gym gear of sneakers, a gray hooded sweatshirt, maroon shorts, a cap and sunglasses.
"Ian went over and asked Hugh if he could take a photograph," Goff tells PEOPLE. "Hugh just went off his head. He walked menacingly past me and chased Ian."
The photographers allegedly ended up on a side street, coincidentally outside the home of Grant's former partner, newlywed Elizabeth Hurley.
Goff says Grant then "got a container of food, it was like Tupperware, and threw it at Ian. It sprayed everywhere and beans ended up in my hair too."
A spokesman for Grant was not immediately available for comment, but Reuters reports the actor's London lawyers said that an incident had taken place and was now under investigation.
Meanwhile, a police insider ponders how successful a prosecution may be over the alleged food-throwing incident. "The evidence may have been eaten," the source tells PEOPLE.