26-year-old nabbed after video shows her giving online personality Vladlen Tatarsky a bust of himself, which investigators suspect hid explosive; suspect denies she knew contents

Vladlen Tatarsky, from Russian-occupied Donetsk, has 500,000 Instagram followers; group that hired cafe calls incident 'terrorist attack'

Emily Mulner traveled to Saint Petersburg to participate in a special program but was detained two weeks ago, a day before her scheduled return to Israel

As all allies of opposition figure Alexei Navalny are barred from running in local and regional elections, some say vote has lost legitimacy