Former Enron Corp. chiefs Kenneth Lay and Jeffrey Skilling were convicted Thursday of conspiracy to commit securities and wire fraud in one of the biggest business scandals in US history. The verdict put the blame for the demise of what was once the nation's seventh-largest company squarely on its top two executives. It came in the sixth day of deliberations following a trial that lasted nearly four months. Lay was also convicted of bank fraud and making false statements to banks in a separate trial related to his personal banking. Lay was convicted on all six counts against him in the trial with Skilling. Skilling was convicted on 19 of the 28 counts against him, including one count of insider trading, and acquitted on the remaining nine. "You have reflected on this evidence for the last few days and reached a very thorough verdict, and I thank you," US District Judge Sim Lake told jurors. He set sentencing for Sept. 11.