Two more of the 10 suspected spies held in the US have admitted they are Russian citizens, prosecutors say.
Michael Zottoli and Patricia Mills say their real names are Mikhail Kutzik and Natalia Pereverzeva, court papers say.
They and a third suspect, Mikhail Semenko, appeared in court in Virginia briefly on Friday.
Another man, Juan Lazaro, was already said to have admitted to prosecutors that he works for Russia's intelligence service.
The 10 are accused of conspiracy to act as unlawful agents of a foreign government, a crime less serious than espionage but which carries up to five years in prison.
Earlier, US Secretary of State Hillary Clinton played down speculation that the affair could cool the warming relations between Washington and Moscow.
"We're committed to building a new and positive relation with Russia," she was quoted as saying during a visit to Ukraine. "We're looking toward the future".
Moscow initially reacted angrily to the claims but has subsequently said the affair will not harm relations.
In Virginia, the couple living under the names Michael Zottoli and Patricia Mills had fake passports and about $100,000 (£66,000) in cash, prosecutors say.
The items were being stored in safety deposit boxes along with other false identity papers, they say.
The couple were detained in Arlington, where they were living with two young children.
Bail granted
On Thursday, journalist Vicky Pelaez was granted bail in New York after the judge said she was a US citizen and did not appear to have been trained as a spy.
However, the judge ordered that she should not be freed before Tuesday, allowing time for a possible appeal by prosecutors. She will remain under house arrest under a $250,000 (£165,000) bond and will be electronically monitored.
Nine other suspects remain in custody in the US.
Mikhail Kutzik, Natalia Pereverzeva and Mikhail Semenko, who appeared in court on Friday, waived their right to a detention hearing, AP reported. They were ordered to be detained and their preliminary hearing was set for Wednesday.
An 11th man, who went on the run in Cyprus on Wednesday after skipping bail, is believed to have fled the island, the Associated Press news agency quoted the Cypriot justice minister as saying.
Christopher Metsos, suspected of being the group's paymaster, was now unlikely to be caught, said Lucas Luca.
Earlier, the US embassy denied local media reports that Mr Metsos was being held at its compound.
'Femme fatale'
In the UK, a man has described how he was married to one of the suspects, Anna Chapman.
Alex Chapman was quoted as saying that Ms Chapman had admitted that her father had once been a senior officer in the KGB.
He told the Daily Telegraph newspaper he had met Ms Chapman at a London party in 2002 and married her five months later.
Ms Chapman, 28, has been painted as the femme fatale of the alleged spy ring, with several glamorous photos posted on her page on Facebook.
The US says its investigation into the alleged spy ring has lasted more than a decade.
