India, Sept. 1 -- A 43-km journey by a private sleeper bus through Greater Noida and Delhi, during which a 16-year-old girl was allegedly gang-raped, has exposed glaring gaps in roadside surveillance and policing, with investigators finding just two proper checkpoints along the route, officials said.

A senior police officer privy to the investigation said the entire route, from Pari Chowk to Kashmere Gate, is being mapped to ascertain the availability of police checkpoints, barricades, CCTV cameras and other surveillance mechanisms along the 43-km stretch.

"We got to know that the first checkpoint was a few metres away from Pari Chowk. There was a police booth and heavy barricading installed along the roadside," the officer said, reques...