NEW ORLEANS (AP) — A second ex-New Orleans officer has been charged in a conspiracy to cover up a deadly police shooting of unarmed residents after Hurricane Katrina.

The shootings on the Danzinger Bridge killed two and wounded four others. The federal charge of misprision of a felony, which means misconduct, was unsealed Tuesday against ex-detective Jeffrey Lehrmann. Lehrmann is now a U.S. Immigration and Customs Enforcement agent in Arizona.

Police are accused of fabricating witness statements, falsifying reports and planting a gun in an attempt to make it appear the shootings were justified.

Michael Lohman, a retired lieutenant, has pleaded guilty to conspiring to obstruct justice.