By Jim Melwert, Syma Chowdhry and Matt Rivers
DREXEL HILL, Pa. (CBS) -- Police say a man suspected of killing his wife in Drexel Hill, Pa. and then abducting two young children took his own life hours later in New York City.
Upper Darby police superintendent Michael Chitwood said 31-year-old Keith Belajonas was found dead in his car on Staten Island, in an apparent suicide.
The incident began when, police say, neighbors heard gunshots this morning around 2:30am at a home on the 200 block of Abbey Terrace, in Drexel Hill.
The Amber Alert rippled through cell phones across the area just before 5 a.m., as people throughout the Philadelphia area were told to be on the lookout for a grey Nissan pathfinder. Just hours earlier, Joseph Galloway saw that SUV drive off his block.
"I didn't see the kids, I think he was already in his truck, he then he took off or whatever and before you knew it, police were all around here," said Galloway.
He didn't know it at the time, but he watched as his neighbor, Keith Belajonas, sped off with his four and five year old sons, moments after police say he shot and stabbed his wife Christine Belajonas, killing her inside their home.
"He really didn't seem like that kind of a guy, him and his wife just kept to themselves," said Galloway.
When police arrived, they found a woman, identified as 28-year-old Christina Belajonas, dead with a gunshot wound to her head and multiple stab wounds.
Investigators say after shooting Christina Belajonas, Keith Belajonas abducted the woman's children, ages five and four.
Chitwood said neighbors heard Belajonas in the stairwell, leaving with the kids after the shooting.
All signs also indicate the two children watched as their mom was murdered.
"One of the children was heard saying, 'Is mommy dead?' " Chitwood recounted later.
Belajonas made his way up to Staten Island, New York, where, investigators, say he held up his brother, who works at a CVS Pharmacy. Chitwood said Belajonas took cigarettes, money, and beer.
Belajonas previously had a minor weapons arrest in New York.
Police say he left the kids behind and fled the scene. The two boys were taken to a hospital in New York as a precaution.
A short time later, investigators say, Belajonas was spotted and police swarmed around his location.
"He then leaves the kids there, and goes not too far away and they find his car on a street up in Staten Island," said Superintendent Mike Chitwood, of Upper Darby Police.
Chitwood says it all seemed to start with an argument.
"He posted on his Facebook, which apparently is a private posting, words similar to, 'We had an argument, she was cheating on me. I won.' "
One neighbor says they heard the couple arguing just a few days ago.
Police say Belajonas and his wife had been married for three years and had lived in the Drexel Hill home for nearly two years.
Christina grew up in Delaware County, and worked at a nursing home as a nurse's assistant until a week ago. Her neighbors remained heartbroken over her death.
"It's horrifying, come on there's two little children involved, two little children who lost their mother," said Kim Billie, who lives nearby.
Authorities expressed concern for the children's well-being, saying they were living in deplorable conditions before the shooting.
"It was just filthy, filthy dirty. You wouldn't want to live there: cat urine, the smell of cat urine. I don't know where the two little kids slept."
Police said they believed Christina Belajonas' father would take in the two boys.
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