Lawyers for 100 survivors and relatives of victims of the deadliest shooting in Maine history have begun the formal process of suing the U.S. Army for what they say was a failure to act to stop the reservist responsible for the crime,

A group of survivors and relatives of victims said the military failed to respond to warning signs from the gunman, an Army Reserve grenade instructor, ahead of the shooting.

More than 100 family members and survivors of Maine’s worst mass shooting are planning to file a lawsuit against the U.S. Army for failing to respond to warning signs that the reservist shooter was a threat.