Arzumanian told RFE/RL from the Yerevan facility where he is being held that "I didn’t do anything that could have been in conflict with the law. This is a political persecution."
Armenian authorities arrested Arzumanian on May 7, just days before parliamentary elections, after accusing him of using money from a Moscow-based businessman to fund opposition activities in Armenia.
Arzumanian is the leader of the Civil Disobedience opposition movement and is closely associated with Armenia's radical opposition bloc, Impeachment.
In his interview with RFE/RL, Arzumanian described his detention at a former KGB prison.
"During the 20 days that I have been here, nothing has happened. I am just isolated, he said. "Perhaps they [the authorities] also understand that there are no facts. This is an extraordinary form of persecution."
Armenian Opposition parties have condemned Arzumanian's detention, describing it as an attempt by the government to silence its opponents.
The pro-Western opposition party Heritage, which was elected to the new parliament, issued a separate statement on May 28 demanding the immediate release of Arzumanian.
Arzumanian served as foreign minister under President Levon Ter-Petrossian from 1996-98 and is an outspoken critic of current President Robert Kocharian’s government.
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