SAN DIEGO - The mystery surrounding a Toyota Prius whose driver reported a stuck accelerator deepened Sunday as the motorist's attorney dismissed a congressional memo that questions his client's version of events.

The memo said technicians with the National Highway Traffic Safety Administration and Toyota could not duplicate the sudden, unintended acceleration that James Sikes said he experienced March 8 when he reached 94 mph on a California freeway.

Kurt Bardella, a spokesman for the committee's top Republican, Darrell Issa of California, said Sunday that the findings "certainly raise new questions surrounding the veracity of the sequence of events" reported by Sikes.