London Helicopter Crash Leaves 2 Dead and Many Unanswered Questions

Two are dead in the wake of a helicopter crash after it struck a crane atop a luxury skyscraper in the center of London during the morning's rush hour commute.

Police have stated that the pilot was by himself when the collision happened, and revealed it was on a scheduled commercial flight from Surrey, which is just to the southwest of the city. Police added that the second person killed was found to be close to the scene, but a London Ambulance Service spokeswoman gave no further details.

The helicopter hit a crane working on the top of the St. George Wharf Tower, also known as the Vauxhall Tower. Upon completion, it will be one of the tallest residential buildings in Europe, according to the site's developers, the Berkeley Group.

"I was standing outside having a cigarette when I saw the helicopter flying super fast towards the crane," Rezart Islami, a builder who was working across the street from the 52-story building, told CNN. "The pilot appeared not to have seen the crane because the helicopter hit it and went bang … the top off the crane also came off in the impact. It all happened so fast it was unbelievable."

After the helicopter plummeted to the ground and burst into flames, firefighters were called to the scene.

London Fire Brigade station manager Bruce Grain explained that the while there was panic in the streets, the burning wreckage was put out within half an hour.

A total of eight fire engines, four fire rescue units and about 60 firefighters along with police officers secured the location and directed traffic.

"We could hear all the sirens and you could smell the smoke as the train went past the site," Christopher Jen, who works nearby, told CNN's iReport. "The station announcers did tell us that there was a helicopter crash at Vauxhall and the engineers had to go check the tracks before we could leave."

Officials have not released the cause of the crash as the investigation is ongoing, but conditions were poor with heavy fog and low visibility and they may have contributed to the crash.