MOSCOW, May 30 (RIA Novosti) - A Moscow district court upheld Wednesday an extension of a criminal investigation into activities of a U.S.-based non-governmental organization in what appears to be a coordinated effort to shut down the group.

A criminal probe into the Educated Media Foundation, the successor of media development organization Internews, was launched in January after British national Jillian McCormack and Russian Manana Aslamazyan were detained in the so-called green channel at Moscow's Sheremetyevo Airport with excessive undeclared cash on them.

Investigators said the women were carrying some $27,000, while Russian law only permits up to $10,000 per person to be brought in undeclared.

The group's defense appealed an earlier court decision to extend the investigation until June 4, but the Tverskoi district court quashed the appeal Wednesday without pressing charges against Aslamazyan, who is still considered a suspect and faces a fine or up to five years in prison if convicted of smuggling.

Police raided the office of the Educated Media Foundation in April, confiscating financial and accounting documents. The raid sparked fears of a possible clampdown on foreign-connected NGOs ahead of parliamentary and presidential elections under a restrictive law adopted last year.

Russian tax authorities froze the group's accounts held in Russian banks last week citing previous violations in tax reporting, while the organization had already suspended all of its activities in the country.

Aslamazyan, who is currently in Paris, denied committing any tax documentation violations.

"We have actually over-paid our taxes and have proof of that," she said. "I do not understand who does not want us [Educated Media] to be in the country."

The new law on NGOs prohibits such organizations from using foreign funds for political purposes. Foreign-funded NGOs were crucial players in 'color revolutions' in Georgia in 2003 and Ukraine in 2004.