Det Sgt Peter Ritson says there was no evidence of a cause of death.
He said the field where Becky's remains were found was a hard soil. She was buried in only 8 inches of soil.
The Oxfordshire coroner Darren Salter recorded a narrative verdict.
On the available evidence its very likely that her death was unnatural and violent. At an unknown location at the end of 2002 or early 2003. “
More top news
Cameron in confident mood as he talks to Bob Constantine at the Tory party conference in Manchester.
The former endurance athlete Mike Buss has denied he stole money from funds he was raising for Help For Heroes.
What would you do if a UFO appeared in the skyline above Bristol? That's the dilemma facing a group of people in a new online mini-series.