A New Jersey mother shot all three of her children, killing two of them, before turning the gun on herself, state police said Friday.

Their announcement confirmed what officials had hinted at, but not spelled out, after a relative's horrific discovery of the family, all found wounded in the same bed, on Thursday morning.

State police Capt. Stephen Jones said there is more investigating to be done in the case of 44-year-old Jeannine LePage, but authorities wanted to share what they know so far "to allay any fears" about a killer on the loose in Tabernacle, a town in the New Jersey Pinelands that's 30 miles east of Philadelphia.

State police Detective Geoff Noble said LePage used a handgun that had been purchased legally and was in the family for decades. He said she used a pillow to muffle any noise so the five other relatives who lived with them wouldn't hear the murder-suicide attempt.

Authorities have not said what prompted the mother to shoot her children. "We may never know with certainty, depending on the condition of LePage, what that motive was," Jones said. "That's something we're not prepared to address right now."

Fourteen-year-old Nicholas Harriman and 8-year-old Nadia were killed. Their 11-year-old brother, Alexander, was wounded. Like his mother, he was at Cooper University Hospital in Camden. Officials described them both as being in "extremely critical condition," suggesting that they are not expected to survive.

After autopsies of the two children, police were able to narrow the timeframe of the shooting to somewhere between 5 a.m. and 9 a.m. Thursday.

The family's next-door neighbor, Jeanne Snedeker, was upset by the shooting, particularly Nadia's death.

"It's hard for me when I sit in my sunroom and look out my window," Snedeker said Friday. "I can picture her running by and waving."

Snedeker said the girl was outgoing and always smiling. She said she did not know their mother well. She did recall a conversation they had in the past year or so about their mutual interest in rescuing animals.

About 200 people attended a candlelight vigil for the family Thursday night in Tabernacle. (AP)