SEATTLE (Reuters) - A Russian accused of hacking U.S. retailers' computer systems to steal credit card data has been ordered by a Washington State judge to be held pending his trial in October, citing risks that he could flee the country, prosecutors said.

The arrest of Roman Seleznev, the 30-year-old son of a deputy in Russia's lower house of parliament, has increased tensions between the two countries, already at their worst since the end of the Cold War over the Ukraine crisis.

Shortly after Seleznev's arrest was announced last month, the Russian Foreign Ministry said his capture amounted to kidnapping and accused the United States of violating a bilateral treaty.

Russia has demanded his immediate release.

Attorneys for Seleznev asked that he be released from custody to his Seattle apartment until the trial, U.S. Attorney Jenny Durkan said in a statement on Friday.

It said Magistrate Judge James P. Donohue denied the request because Seleznev was a frequent international traveler, had access to money in bank accounts around the world and had the ability to forge fake identity documents, making him a flight risk.

Seleznev faces charges including bank fraud, causing damage to a protected computer, obtaining information from a protected computer and aggravated identity theft, prosecutors said.

His indictment said Seleznev hacked into retail point of sale systems to steal credit card numbers from 2009 to 2011.

The man's father, Valery Seleznev, a deputy in Russia's lower house, said in a statement last month that he intended to take every step to protect his son.

"The defendant is entitled to every protection offered by our system, but will be afforded no special privileges," Durkan, U.S. Attorney for the Western District of Washington, said in the statement.


(Reporting by Eric M. Johnson in Seattle; Writing by Curtis Skinner in New York; Editing by Alison Williams)