It was working on strengthening circuit breakers meant to prevent disorderly stock market runs, U. S. Securities and Exchange Commission has said.

It has been reported that SEC Chairwoman Mary Shapiro met with leaders of the six major U. S. markets, including the New York Stock Exchange, Nasdaq and the Chicago Board of Options Exchange, Monday to review Thursday's sudden market plunge that saw the Dow Jones industrial average drop nearly 600 points in 15 minutes.

The New York Times has reported that circuit breakers are meant to slow such an event but regulators are examining the possibility that safety mechanisms backfired.

Leaders of the stock exchanges and the Financial Industry Regulatory Authority "agreed on a structural framework ... for strengthening circuit breakers and handling erroneous trades," the SEC said.

There was no evidence that computers had been sabotaged. Similarly, many analysts have ruled out the possibility that a single large sell order triggered the plunge, the U. S. Department of Homeland Security further said.

"The technology has gotten ahead of the regulators," U. S. Sen. Richard Shelby, R-Ala., the ranking Republican member of the banking committee, said on Sunday.

He further added, "Regulators have got to get ahead of the technology. That is going to be a big challenge down the road." (With Inputs from Agencies)