(Newser) – One more twist in this week's bizarre story of a New York City driver getting assaulted by a group of motorcyclists in broad daylight: It looks like an undercover NYPD detective was there the whole time but chose not to intervene, reports the Daily News. The detective had been riding with the bikers and didn't want to blow his cover, though he wasn't investigating a specific crime, says the newspaper. He came forward days after the Sept. 29 assault and is now on restricted duty while an investigation takes place, reports the New York Post. It adds that other off-duty cops might have been present.

The AP has the story, too, but it says investigators still aren't sure whether the detective actually witnessed the beating. It took place last weekend after dozens of bikers stopped an SUV and pulled the driver out after he had struck a motorcyclist in their group. That motorcyclist remains hospitalized and might never walk again. The driver needed stitches after the beating. So far, three of the motorcyclists have been charged.