A Lilburn man died after going back into his burning home to save the family dog, just moments after making sure his mother got out safely, Gwinnett County Fire and Emergency Services said.

Firefighters were called to a house fire Sunday in the 200 block of Sandra Drive just after 6:20 p.m., after a 911 caller reported the home was burning and people were still inside. When crews arrived, they found a heavy fire at the two-story house and were told a man was still inside.

Lilburn police officers helped secure the scene as firefighters rescued one victim from the entryway of the home. Crews then encountered the intense fire in the garage and main living area, which had spread into the attic. Firefighters used multiple hose lines to knock down the flames and searched the home, finding no other victims inside.

Investigators said two people were home when the fire started. One occupant noticed the fire and woke his mother so they could evacuate. A neighbor helped the mother get out of the house before firefighters arrived. After she was safely outside, the son went back inside to rescue the family dog. Officials said he was overcome by heavy smoke and did not survive.

One person was taken to a hospital with life-threatening injuries. A Lilburn police officer suffered minor injuries and was treated and released at the scene. Another individual was also evaluated and released.

Fire officials said the home suffered extensive fire damage to the garage, main living area and attic, along with widespread smoke and water damage. No smoke alarms were active at the time of the fire. Two adults were displaced, and the American Red Cross was called to assist.

A fire investigator responded to determine the cause and origin of the fire. The investigation remains ongoing.