Kira Yarmysh, press secretary of Alexei Navalny, was detained at the police department for the Tverskoy District. She tweeted about it.
As Yarmysh writes, she was detained allegedly for organizing a rally on May 5. She clarifies that she then wrote only one tweet with a link to Navalny's video after the notice was filed. By that time, the mayor's office had not yet refused to approve the action.
UPD 11:00 Kira Yarmysh and Ruslan Shaveddinov are charged with “organizing a rally on May 5 by retweeting,” writes Leonid Volkov.