Former Enron chief executive officer Kenneth Lay has been indicted by a grand jury in Houston, Texas, for his role in a series of accounting scandals involving the company, according to US news reports.

US Magistrate Judge Mary Milloy in Houston acceded to the prosecutors' request and sealed both the indictment and an arrest warrant. The details are expected to be made public on Thursday, when the US Securities and Exchange Commission is expected to file civil charges against Lay, The Wall Street Journal reported.

India knows Enron better for its involvement in the Dabhol power project that began in the early 1990s and the subsequent claims of corruption and price-gouging against the company.

The charges against Lay will include insider trading and infringement of securities laws. He is the thirtieth person to be charged in the case. Former CEO Jeffrey Skilling and senior accountant Richard Causey are among those awaiting trial.

Unlike Skilling and Causey, former chief financial officer Andrew Fastow has already pleaded guilty to charges of hiding Enron's perilous financial situation while making a huge amount of money for himself.

Lay finished a doctorate and began his career as a corporate economist with Exxon. Later, he taught economic theory and government-business relations at universities. Though it is his relationship with President George W Bush that is often cited, he was also a regular golf partner for former president Bill Clinton during his term in office.

Lay's indictment comes over two years after investigations began into the collapse of the Houston-based energy company.