ATTLEBORO – Norton police encountered four screaming children — the youngest just 9 months — at the scene of a brutal murder last night, where the mother of three of them was beaten and stabbed to death after the family had sat down to dinner.

“I just killed my wife. I need to be cuffed,” Martin McDonald, 35, called out to State Trooper Curtis Cinelli on the side of Route 495 last night after allegedly driving his Dodge pickup into oncoming traffic shortly before 7:30 p.m. and hitting a car head-on, according to graphic police reports released today by Attleboro District Court.

The driver of the Nissan, a woman, suffered serious injuries, police said.

Cinelli came upon the crash just as Norton police were making the grim discovery of McDonald’s estranged wife Julie Meede’s body at her apartment on Holmes Street.

Cops had been called to the address by her blood-soaked 10-year-old daughter, who was able to tell a 911 dispatcher her stepfather had attacked her mother even after McDonald smacked the brave girl in the head and took her cell phone, assistant Bristol District Attorney Stephen Nadeau said.

Nadeau said the girl was “indicating that her mother had just been stabbed by her stepfather, and her stepfather had fled in his truck.”

During a subsequent interview, Nadeau said the girl told police that after dinner McDonald had retrieved a large bag of clothes and swung it at Meede’s head, “knocking her to the ground” and punching her in the head before grabbing a knife “and stabbing her multiple times.

“The young girl said she then tried to call 911, at which point the defendant struck her and took her phone,” the prosecutor said.

Nadeau said when McDonald was arrested he was covered in blood and a knife was recovered from his truck “that appeared to be saturated in blood.”

“This was a tough scene that happened,” Norton Police Chief Brian Clark said at the courthouse, where the doomed couple’s stricken-looking family requested privacy.

The daughter, Clark said, “did an amazing job. I think she’s going to have a lot of family support.”

McDonald, a 6-foot, 2-inch, 305-pound electrician, was ordered held without bail and sent to Bridgewater State Hospital for a psychiatric evaluation by Judge Edmund C. Matters after pleading not guilty to murdering his 34-year-old bartender wife and assaulting his stepdaughter.

His public defender Dana Sargent made no argument for bail and declined to speak about the tragedy afterwards.

Court clinician J. Arthur Pearson, a psychologist, told Mathers that McDonald claimed to have a history of hospitalizations for psychiatric problems and had attempted suicide in the past.

Mathers also revoked McDonald’s bail on an open assault and battery case from November, where he was alleged to have kicked another man.

Meede had been arrested for assault and battery in July for allegedly throwing a barstool at McDonald and clubbing him with a pink hammer because she was angry he took their infant son to a restaurant where liquor was served. He accused her of being “violent in the past.”

Meede told police at the time that McDonald “was looking to get into an argument”

McDonald declined to seek out a restraining order against Meede and the case was dismissed last month for lack of prosecution, court records show.

The couple’s two children — a boy, now 9 months, and a girl, now 3 — along with Meede’s 10-year-old daughter and a 5-year-old niece, apparently witnessed her murder, according to court records. Police found them crying in Meede’s living room.

Police reported finding Meede “lying on the floor between the kitchen and living room with several lacerations to her facial area along with lacerations and stab wounds and the lining of her stomach protruding outwards.”

McDonald is next scheduled to appear in court March 2 for a probable cause hearing.