No, but there are a number every year which are sealed for various reasons and later unsealed. The amount in the last year is unprecedented.

John Hubber US Attorney out of Utah and his team are the group behind the sealed indictments.

https://en.wikipedia.org/wiki/John_W._Huber

Huber speaks directly to Sessions and has the ability to form a grand jury unlike like the IG who speaks to Rod Rosenstein. When Sessions recused himself he appointed Huber in his place. Huber's office is in Utah far away from DC and can issue indictments in any state.