The motion to dismiss the charges was filed Friday.
"It was a procedural motion to keep them off the books in order to bring them back under a superseding indictment," said Robbie Sherwood, spokesman for the U.S. attorney's office in Phoenix.
Loughner, 22, is accused of shooting U.S. Rep. Gabrielle Giffords in the head at a "Congress on Your Corner" event at a Tucson, Arizona, grocery store, then shooting 18 other people, six of them fatally. The dead included Giffords staffer Gabe Zimmerman and U.S. District Judge John Roll. Giffords is currently recovering in a Houston rehabilitation hospital.
The initial complaint filed against Loughner had five counts -- one count of attempting to assassinate Giffords; two counts of attempted murder in the shootings of Giffords staffers Pamela Simon and Ron Barber; and two murder charges in the deaths of Roll and Zimmerman.
Loughner Murder Charges Dropped
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