At about 3:15 pm, the car turned into Braybrook Street, a residential road on the Old Oak council estate bordering Wormwood Scrubs and Wormwood Scrubs prison. The officers spotted a battered blue Standard Vanguard estate van, registration plate PGT 726, parked at the roadside with three men sitting inside it. Since escapes were sometimes attempted from the prison with the assistance of getaway vehicles driven by accomplices, the officers decided to question the occupants. It is possible that PC Fox also recognised the van's driver, John Witney, as a known criminal. The vehicle also had no tax disc on display, which was then a legal requirement.