Florida Shooting: Former US army sniper kills four, including a 3-month old baby & dog

A former US military sniper killed four people, including a woman and her three-month-old baby, in her arms, before surrendering to police in central Florida.

The suspect, identified as Bryan Riley, 33, also shot an 11-year-old girl who had to undergo surgery for seven gunshot wounds, Polk County Sheriff Grady Judd declared. The shooter was also high on methamphetamine, the police said.

Riley, who had no connection to the victims, also had an intense shootout with police before giving up. He later tried to grab a police officer's gun while he was being treated at the hospital for his own gunshot injuries. He told police that people "begged for their lives but, I killed them anyway,"

A veteran of the US wars in Iraq and Afghanistan, Riley worked as a bodyguard and security guard.

The attacker's girlfriend told police that he had been undergoing post-traumatic stress disorder and depression. She said Riley's mental had been getting worse day by day, and he claimed he could also "talk to god".

The assailant first appeared by chance at the house where the shooting took place on Saturday night, making senseless statements, but left as police responded.

He returned early on Sunday to kill a 40-year-old man and the 33-year-old mother and her baby, Polk County Sheriff Grady Judd stated. In the house next door, he also killed the 62-year-old mother of the woman. She also shot dead their dog, police said.

After people reported sounds of automatic rifles, the police discovered the assailant outside in the street, unarmed, wearing a camouflage T-shirt and vest.

Deputies, who responded to reports of two volleyball automatic rifles, arrived to find the suspect armed outside, with camouflage and body armour.