Argentina's former President Cristina Fernández is in court for the first in a series of corruption trials.

Security agents cordoned off the federal court room in Buenos Aires as Fernández arrived Tuesday. She is accused of embezzlement in public works projects during her 2007-2015 presidency. She denies any wrongdoing.

Fernández was widely expected to run for the presidency against conservative President Mauricio Macri during the October election.

But she surprised Argentines over the weekend announcing she'll seek the vice presidency, with her former Cabinet chief Alberto Fernández at the top of the ticket.

Her running mate also served briefly served under her late husband and predecessor, Nestor Kirchner, and is now one of the at least 150 witnesses in the case.