Kocharyan, who served as Armenia’s second president from 1998 to 2008, was in court and taken into custody, the lawyer, Aram Orbelyan, added.
Kocharyan has dismissed the charges as politically motivated.
Investigators have charged Kocharyan with an attempt to overthrow the constitutional order during events after the 2008 elections when his ally Serzh Sarksyan became the next president.
In February-March 2008 the opposition held protest rallies, contesting the results of the election and saying that their candidate, Levon Ter-Petrosyan had won the vote.
The protests were dispersed and 10 people were killed in clashes with police. The Constitutional Court upheld the election results.
Nikol Pashinyan, an opposition activist at the time who was imprisoned in June 2009 on charges of fomenting unrest during post-election protests, was elected prime minister by parliament on May 8 this year.
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