3 Are Arrested in Theft of Gold Helmet from Dutch Museum

Sometimes uses of "to be" make me pull up short.

This headline has one of those uses. "3 are arrested" - the "are" is almost superfluous. "3 arrested" works identically, and is 3 characters shorter, something that is said to be prized in headlines.

If the "3 are arrested" is deliberate and not sloppy, the phrasing raises the question "who arrested those 3?" The use of a "to be" verb makes the arrest magical in its vagueness.