More families who lost loved ones in the Virginia Beach mass shooting are calling for an independent investigation.

The Virginian-Pilot reported Tuesday that three victims' families also want the city to release more information.

Civil engineer DeWayne Craddock opened fire in a municipal building May 31 and killed 12 people. He died in a gunfight with police.

Debbie Borato, the sister of victim Missy Langer, said her family can't fully mourn without knowing more about what happened. Two sisters of victim Joshua O. Hardy's also want more information.

They join the husband of victim Kate Nixon. Jason Nixon said his wife had concerns about Craddock before he carried out the attack.

City officials have said the appropriate time to discuss an independent probe would be after the criminal investigation concludes.

Information from: The Virginian-Pilot, http://pilotonline.com