MARY Ann Holder wanted to see her married old flame one last time as their bitter love triangle threatened to open a new and potentially costly chapter in court. The meeting ended with Mr Randall Lamb, 40, being shot and Ms Holder, 36, taking her own life on Sunday.

Later, police found that Ms Holder had shot five children, including her two sons and the older boy's girlfriend, AP reported.

On Monday, her son Zachary Smith, 14, became the third child to die in the incident. He succumbed to gunshot injuries in a hospital in Greensboro, North Carolina in the US, authorities told New York Daily News.

The other two were her son, 17-year-old Robert Dylan Smith and her niece, Hannaleigh Suttles, eight.

Investigators are trying to unravel the violent chain of events and understand why Ms Holder took out her rage on children. She left two suicide notes taking responsibility for the shootings, Guilford County Sheriff BJ Barnes said.

The notes also indicate she was angry about how her relationship with Mr Lamb ended.

She wrote that she was sorry for the pain she caused and then took her own life inside her parked Ford Explorer on Sunday morning.

Investigators said Ms Holder and Mr Lamb had been having an affair for almost four years, and it was grinding to an acrimonious end.

In February, Mr Lamb's wife, Jennifer, sought a court order to keep Ms Holder away from her and her husband. Mrs Lamb stated in the complaint that Ms Holder would constantly call and send SMSes and nude pictures of herself.

Shot multiple times

Authorities said Mr Lamb agreed to meet Ms Holder at a community college carpark that Sunday. There, Ms Holder shot at him multiple times and hit him once in the shoulder, the sheriff said.

Mr Lamb called his wife, who reported the shooting to emergency service 911.

He is in stable condition now.

Ms Holder then drove off to pick up Zachary who had stayed over at a friend's house the previous night.

Nearly half an hour later, a sheriff's deputy on the lookout for Ms Holder's black SUV drove past it and turned around after seeing what he thought was a puff of smoke inside the vehicle.

Ms Holder was found dead inside with a gunshot to the head, and Zachary, critically wounded, was in the back seat. Two handguns were recovered from the car.

The officers then went into Ms Holder's home and found Robert dead and his girlfriend Makayla Woods, 15, seriously hurt. She is now on life support. Ms Holder's nephew, Richard Suttles, 17, were also shot inside the home and is in critical condition.

The victims appeared to have been shot while they slept in a bedroom and the home's living room, the police said.

The dead children were kind and vigilant toward the elderly couple across the road, a neighbour, Teresa Scott, told AP. They volunteered to help with yard maintenance and inquired about the health of her husband, Joe, who has had recent health problems.

Said Sheriff Barnes: "We've got death. We've got drama. We've got a situation basically no one could ever imagine."

This article was first published in The New Paper.