A US federal grand jury in Omaha, Nebraska, has indicted three Indians on charges of hacking into online brokerage accounts of others using stolen usernames and passwords for making big time profit.

The 23-count indictment unsealed Monday charged Jaisankar Marimuthu, 32, and Chockalingam Ramanathan, 33, both residents of Chennai, each with one count of conspiracy, eight counts of computer fraud, six counts of wire fraud, two counts of securities fraud, and six counts of aggravated identity theft as part of this what the justice department dubbed as "hack, pump and dump" scheme.

The indictment also charged Thirugnanam Ramanathan, 34, a native of India and resident of Malaysia, with one count of conspiracy, two counts of computer fraud, and two counts of aggravated identity theft.

While Marimuthu and Ramanathan have been arrested, Chockalingam Ramanathan is still at large.

As part of this ongoing investigation, at least 60 customers and nine brokerage firms in the United States and elsewhere have been identified as victims, with one of the brokerage firms reporting more than $2 million in losses.

The case marks the first time that individuals have been arrested overseas in connection with an online brokerage intrusion scheme perpetrated in the United States, the justice department said. In a related action, the SEC filed a civil complaint against all three defendants in federal court in Nebraska.

"These new forms of high-tech identity and securities fraud pose serious risks to investors and brokerage firms across the globe," said Assistant Attorney General Fisher.

"Today's case demonstrates our commitment to aggressively investigate and prosecute these schemes wherever they originate. I commend the investigators and prosecutors in this case for their tremendous cooperation and speedy action to track the source of this scheme halfway around the world."

According to the indictment, between July and November 2006, the defendants, operating primarily from Thailand and India, used their personal online brokerage accounts to purchase shares of several thinly-traded stocks.

They then hacked into online brokerage accounts of others using stolen usernames and passwords or established new brokerage accounts using stolen identities. Using these accounts, the defendants made scores of unauthorised purchases of the same stocks to drive up the market price.

Once the share prices were artificially inflated, the defendants sold their own shares for a substantial profit.

In one of many examples alleged in the indictment, Marimuthu placed orders on August 28, 2006, through his personal online brokerage account, to purchase 32,000 shares of stock in a company at prices from $2 to $3.20 per share.

Chockalingam also placed an order through his personal online brokerage account to purchase 450 shares of the same stock for $3.20 per share.

The same day, the defendants gained unauthorized access to the online brokerage account of an unsuspecting investor. According to the indictment, the defendants used this account to illegally acquire 26,000 shares of the same stock at prices from $2.84 to $3.40 per share, causing the stock's trading volume to rise to more than nine times its 15-day average.

Marimuthu then placed an order to sell 1,500 shares of the same stock from his personal online brokerage account at five dollars per share. This was one of at least 22 sell orders for this stock placed in Marimuthu's personal online brokerage accounts between Aug. 28, 2006, and the morning of Aug. 29, 2006. These transactions allegedly resulted in the sale of 30,700 shares of this stock, yielding a substantial profit for the defendants over the course of just a few hours. The defendants used this type of scheme with various stocks between July and November. 2006.

"Although the basic concept behind the fraud alleged in the indictment is simple, the methods employed were sophisticated. The investigation, therefore, required a savvy understanding of high-tech transactions and an ability to communicate and cooperate internationally. The Justice Department's Criminal Division, the FBI, and the SEC, are to be commended for the coordinated effort with international law enforcement that resulted in this Indictment and the apprehension thus far of two of the three defendants," said U.S. Attorney Stecher.

"Hackers who prey on American investors -- no matter what continent they're operating from -- are meeting their match with powerful adversaries in the Department of Justice and the Securities and Exchange Commission. We will go anywhere on earth to stop these thieves and hold them accountable," said SEC Chairman Christopher Cox. Marimuthu was arrested on Dec. 20, 2006, by the Hong Kong Police on charges of computer fraud, money laundering, and possession of equipment to make a false instrument.

These Hong Kong charges concern crimes similar to those charged in the U.S. indictment. Thirugnanam Ramanathan was arrested by authorities in Hong Kong on Jan. 26, 2007, pursuant to a U.S. provisional arrest warrant.

Chockalingam Ramanathan is at large. The government said it would seek the extradition of the arrested defendants to face charges in Nebraska.