Father kills 2 sons, injures another

Police received several 911 calls from neighbors after they heard screams coming from the north Syracuse house

SYRACUSE, New York (CNN) -- Police in Syracuse, New York, searching for a motive in the stabbings of three children by their father, said they hope to get more details from the mother on Monday.

Two of the boys were killed and the third is in critical condition from the attack Saturday night. The mother was hospitalized for shock.

Police want to know why the father, Cuong Tran, 33, stabbed his sons, ages 5, 6 and 7. Tran was shot and killed by police when he went after the officers with a knife, police said.

Police Sgt. David Sackett said it was difficult to determine a motive.

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Kim Cao, a sister of the children's mother, said Tran had lost his job at a manufacturing company six months ago and had been unemployed since then. A native of Vietnam, he had been in the United States for 13 years, she said.

The mother's brother, Loc Le described Tran as a "good, family-caring guy" whom he had never known to be violent. Asked what may have led to the killings, Le said, "We have no idea. That's what we're trying to find out." He said the unmarried couple had lived together for eight years.

Shane Townley, who lives across the street from the family, told CNN he never saw Tran express anger toward his children.

Danny Tran, 6, and his brother Randy, 5, were found in separate rooms, stabbed to death.

A third child, Andy, 7, was lying in another room with multiple stab wounds, Sackett said. Sackett said the children's mother returned home from a wedding Saturday night to find the doors of the home locked.

Le, who lives upstairs in the two-family home, told CNN his sister looked inside a window and saw her youngest child lying on the floor, bleeding.

Her screams for help were heard by a neighbor, who called police, according to Le. Police said they received several 911 calls from neighbors after they heard screams in the house in north Syracuse.

One caller said he saw children through the windows "motionless on the floor" and a man walking through the house covered in blood, Sackett said.

Sackett said Tran told the mother through the door he was "killing her children." Sackett said he brought one of the dead children to the window to show her.

Police, who arrived at 11:11 p.m. Saturday, broke their way through a door secured by a chain lock and found a child lying motionless on the floor.

Tran was standing inside the room, armed with a knife, Sackett said.

"The suspect came after police with a knife," Sackett said. "They fired one shot, striking Mr. Tran. Mr. Tran was at a later time pronounced dead."

Sackett called the incident the worst he had seen in 28 years on the force. "To see those children laying there was just a horrific, horrific sight." he said.

The incident comes less than two weeks after the arrest of a woman in the drownings of her five children in Houston, Texas.