VIRGINIA BEACH, Va. — A Chicago consulting firm has been chosen to lead an independent investigation into the Virginia Beach mass shooting that left 12 dead.

The Virginian-Pilot of Norfolk reports security risk management firm Hillard Heintze can start the probe immediately after entering into a contract with the city. City Auditor Lyndon Remias, who selected the firm out of 14 other bids, said that should happen by Friday or early next week.

The company has experience in working with mass shootings. Its website says it has done more than 17,000 investigations for major companies and organizations.

City engineer DeWayne Craddock opened fire in his work building on May 31 , the same day he submitted his resignation notice. He killed 12 people and wounded several others before he was gunned down by police.