A woman and two children bludgeoned to death with a hammer in a suburban New Orleans apartment were killed by the woman's boyfriend, authorities said Thursday.

Two other children remain hospitalized following the Wednesday morning attack in Terrytown. Jefferson Parish Sheriff Joseph Lopinto identified the suspect Terrance Leonard, 33, of Gretna.

Kristina Riley, 32, her 10-year-old son, Ayden Riley, and her niece, 9-year-old De'ryona Encalade were killed.

Riley's other daughters, ages 14 and 12, were critically wounded. Leonard was arrested Wednesday on charges that include first-degree murder.

Lopinto said investigators believe the children were attacked in bed as they slept, most likely between midnight and 2 a.m., while Kristina Riley was out with her mother.

"It didn't appear that there was any struggle from any of the locations where the children were," he said.

Leonard, who lived at the apartment, told investigators he waited for Kristina Riley to come home and then killed her at around 2 a.m., Lopinto said.

A neighbor heard an argument in the apartment about that time but did not summon police, Lopinto said. It wasn't until after 7 a.m. Wednesday that someone called authorities to the address, saying people there needed medical attention.

"We obviously found a very gruesome scene," Lopinto said at a news conference.

Leonard was detained at the scene Wednesday and became a suspect as the investigation continued. Lopinto said he confessed Wednesday evening. Investigators found the hammer Leonard is believed to have used in a garbage can after he told them where it was hidden, Lopinto said.

Leonard was being held without bond on the murder charges. Other charges Leonard faces include attempted first-degree murder and obstruction of justice for hiding the hammer and attempting to clean up the scene, authorities said. Information on his attorney was not available.

Riley's father told New Orleans news outlets that Riley was trying to break up with Leonard. Lopinto said he didn't believe that was a motive.

"I really don't believe that there was a motive in this," he added. He said Leonard told investigators he was under the influence of crack cocaine at the time of the attacks. But, Lopinto also cast doubt on that as a factor. "There's a lot of people under the influence of narcotics and this is not a normal situation."

Lopinto said there was no record of domestic violence complaints involving the couple.

A first-degree murder conviction carries a possible death sentence.

"I don't normally get involved with the penalty, by any means. That's going to be a decision of the jury and the judge," Lopinto said, when asked if he would support pursuit of the death penalty. "Would I support it? The answer is yes."