Police said a 37-year-old woman was arrested at the terminal on suspicion of assaulting police. The Metropolitan Police spokesman refused to identify the woman, or say whether the incident took place inside the terminal or aboard a plane. He spoke on condition of anonymity, in line with police policy.
BAA PLC, the company that runs Heathrow, didn't immediately return calls seeking comment. British Airways PLC, the terminal's sole occupant, referred questions to BAA and London police.
Campbell's publicist, Selina Aponte, left Heathrow's police station, where the model had been taken, just before 10 p.m. but told waiting reporters she had not seen the British model, who had been due to fly to Los Angeles.
"We have all seen the reports but I don't know anything," Aponte said. "Naomi was flying to L.A. She has family and friends over there and is always going over."
In January 2007, Campbell pleaded guilty in New York City to misdemeanor assault for throwing her cell phone at her maid in a dispute over a missing pair of jeans. She was ordered to do community service and attend a two-day anger-management program.
Campbell pleaded guilty in Toronto in 2000 to an assault charge for beating an assistant while making a film in Canada in 1998. Under an agreement with prosecutors, Campbell expressed remorse and was released without punishment or a criminal record.