Updated: Amy Winehouse was pronounced dead at her London home on Saturday, July 23.

Sources say emergency services found the 27-year old Back to Black singer unresponsive at the scene. Her cause of death was not immediately known and police currently describe it as being "unexplained."

Authorities were called by the London Ambulance Service in response to a report of a deceased woman in Camden Square. The LAS said Winehouse died before the two ambulance crews it sent arrived at the scene.

Winehouse recently left a British rehabilitation program to prepare for a European concert in June 2011. But the tour was cut short in Belgrade when she reportedly staggered around the stage and stumbled through songs.

She was last seen on a concert stage this week at the iTunes Festival supporting her goddaughter 14-year old singer Dionne Bromfield.

Radar Online reports that an autopsy on Winehouse could take place in the next 24 hours or Monday morning.