LOS ANGELES, US (Reuters) - Over 1,000 Toyota and Lexus owners have reported sudden, spontaneous acceleration of their vehicles since 2001, including crashes blamed for 19 deaths, far more than earlier disclosed, the Los Angeles Times reported on Sunday.

The National Highway Traffic Safety Administration previously has said it had received reports of 100 such incidents, including 17 crashes and five fatalities.

Toyota Motor Corp announced in September that it would recall some 3.8 million vehicles in the United States because of the risk of improper-fitting floormats jamming accelerator pedals in several models.

The recall includes the hot-selling Prius hybrid and would be the largest ever for Toyota, which has built a reputation for safety and quality that had helped it surpass General Motors Co as the world's leading automaker last year.

But the Times said it had uncovered a problem much bigger in scope from its own examination of thousands of federal defect investigation records, NHTSA complaints filed by car owners, lawsuits against Toyota and reports by independent safety experts and local police agencies.

Owner complaints of runaway Toyota and Lexus vehicles helped trigger at least eight investigations of the problem by NHTSA in the last seven years, but the agency closed six of those cases without finding a defect, the Times reported.

According to the newspaper, federal officials eliminated broad categories of sudden-acceleration complaints, including cases in which drivers said they were unable to stop runaway cars using their brakes; incidents of unintended acceleration lasting more than a few seconds; and reports in which owners did not identify the possible causes of the problem.

By its own count, the newspaper said it found more than 1,000 reports from motorists that their Toyota or Lexus vehicles had suddenly sped up on their own, and records of 19 fatalities in which unintended acceleration may have been a factor in vehicles going back to the 2002 model year.

Independent safety expert Sean Kane, president of Safety Research and Strategies, told the Times he has identified nearly 2,000 such cases.

Most runaway vehicle incidents did not result in a crash. But notable exceptions have included the case of a Lexus ES 350 that sped up to more than 100 mph (160 kph) and crashed near San Diego on Aug. 28, killing an off-duty California Highway Patrol officer who was driving and three members of his family.

In a written statement, the Times said, NHTSA said its records now show that a total of 15 people died in crashes related to possible sudden acceleration in Toyota vehicles from the 2002 model year or newer, compared with 11 such deaths in vehicles made by all other automakers.

"The NHTSA takes every allegation of safety problems seriously," the agency said in a statement to the Times. "In the case of complaints about sudden acceleration in Toyota vehicles NHTSA moved very quickly to respond to them."

Toyota defended its vehicles and the validity of prior NHTSA investigations as "exhaustive."

"In each case, the agency closed the investigation without finding any electronic engine control system malfunction to be the cause of unintended acceleration," the company said in a statement to the Times.