POLK COUNTY, Fla. (AP) — Four people are dead including a mother still cradling her now-deceased baby after a massive gunfight early Sunday with a former Marine a Florida sheriff said was “ready for battle” and so aggressive he tried to wrestle a gun from police from his hospital gurney after being captured.

Polk County Sheriff Grady Judd said 33-year-old Bryan Riley appeared to be suffering from mental health issues and had been slowly unraveling for weeks, repeatedly telling his girlfriend that he could communicate directly with God.

After a gunfight with police and deputies — where dozens “if not hundreds of rounds” were exchanged outside a Lakeland home, Judd said, authorities found an 11-year-old girl shot multiple times, plus four deceased victims. They included a 33-year-old mother still holding her 3-month old baby boy and the infant’s 62-year-old grandmother who lived at a neighboring home, and a 40-year-old man.

Riley, who served as a sharp shooter in both Iraq and Afghanistan, seemingly targeted the family at random, Judd said during a press conference Sunday.

Preliminary evidence shows the 40-year-old Justice Gleason just happened to be an unlucky stranger out mowing his lawn Saturday night when Riley drove by, saying God told him to stop because Gleason’s daughter was going to commit suicide.

A second person came to confront Riley, telling him that story wasn’t true and warned they would call police if he didn’t leave, Judd said. Authorities responded to the scene but never found Riley.

About nine hours later, around 4:30 a.m., Riley returned to the home, laying out glowsticks to create a path leading to the house to draw officers “into an ambush,” Judd said.

By chance, a lieutenant far in the distance, heard popping noises and immediately put the agency on active-shooter mode, bringing all state and local law enforcement in the area to the scene.

Following the sounds of gunfire, authorities arrived at the home and found Riley’s white truck ablaze and an unarmed Riley outside, dressed in camouflage.

Riley immediately ran inside, where authorities heard another round of gunfire, “a woman scream and a baby whimper,” Judd said.

Officers tried to enter the front of the house, but it was barricaded. When they circled to the back, they encountered Riley, who appeared to have put on full body armor including head and knee coverings and a bulletproof vest.

Authorities exchanged heavy gunfire, before Riley retreated back into the home, according to the sheriff.

Everything fell silent, Judd said, until a helicopter unit alerted authorities on the ground that Riley was coming out. He had been shot once and was ready to surrender.

Meanwhile, officers heard cries for help inside the home, but were unsure whether there were additional shooters and feared the home was booby-trapped. A brave sergeant rushed in and grabbed an 11-year-old girl who had been shot at least seven times.

She told deputies there were three dead people inside, Judd said, adding that she was rushed into surgery and was expected to survive.

Deputies sent robots into the home to check for explosives and other traps. When it was clear, they found the unidentified mother and baby, Gleason and the family dog all dead from gunshot wounds. The baby’s grandmother was also found dead in a home out back. Authorities did not say if or how Gleason was related to the other people in the home.

“They begged for their lives and I killed them anyway,” Judd said Riley told them during an interrogation, adding Riley was playing mind games during the interviews with detectives.

Authorities declined to say how many times the victims had been shot or where they were in the home, but said they were all hiding and huddling in fear.

Authorities said Riley’s girlfriend of four years, who he also lived with, had been cooperative and was shocked, saying he was never violent but suffered from PTSD and had become increasingly erratic.

She said he’d spent the previous week on what he called a mission from God, stockpiling supplies that he said were for Hurricane Ida victims, including $1,000 worth of cigars.

“Prior to this morning, this guy was a war hero. He fought for his country in Afghanistan and Iraq,” said Judd. “And this morning he’s a cold-blooded killer.”

Riley, who had no criminal history, also told authorities he was on methamphetamines. His vehicle had also been stocked with supplies for a gunfight, authorities said, including bleeding control kits.

While being treated at the hospital, Riley jumped up and tried to grab an officer’s gun. “They had to fight with him again in the emergency room,” Grady said, before he was ultimately tied down and medicated.

He is expected to recover and will be transferred to jail to face charges.

“The big question that all of us has is, ‘Why?'” State Attorney Brian Haas said. “We will not know today or maybe ever.”

This story corrects a reference to the number of people killed. There were four, not three. It also clarifies a reference to one of victims. The infant’s grandmother is 62 years old and lived in a nearby home.