HACKENSACK, N.J. (AP)  -- A fight over money led to the stabbing deaths of three North Jersey family members by a Long Island man, authorities said Monday.

1010 WINS VIDEO: N.Y. Man Charged with Killing 3 in N.J.

Kang-Hyuk Choi, 32, of Valley Stream, N.Y., was charged with three counts of murder in the killings of Doo Soo Seo, 70; Seo's sister-in-law, Yoo Bok Kim, 47, and Kim's son, 27-year-old Han Il Kim.

1010 WINS AUDIO: Steve Sandberg reports

Their decomposing bodies were found Friday in their home in Tenafly, an upscale suburb about 10 miles from New York City.

Choi was arrested Sunday in California. He waived his right to an extradition hearing and was expected to be on a plane back to New Jersey by Monday evening, Los Angeles County District Attorney's Office spokeswoman Shiara M. Davila said.

It was unclear on Monday if Choi had an attorney.

Investigators said they tracked down Choi using clues from a diary Han Il Kim kept, detailing everything from what he ate and what time he woke up to what he did with his friends.

``This was just great police work,'' said Frank Puccio of the Bergen County Prosecutor's Office. ``We didn't even have identities of these people and we solved it 36 hours later; it doesn't get better than this.''

Authorities say Choi quarreled with Han Il Kim -- a young cell phone store entrepreneur -- over money after spending a weekend socializing with him on May 3 and 4.

Choi stabbed Han Il Kim multiple times, prosecutors say, and hid his body in the closet of his bedroom at his Kim family's Tenafly home. Puccio said Choi waited several hours in the home -- even stuffing Kim's bedsheets with clothing to make it look like he was sleeping there -- before killing Kim's mother when she came to check on her son.

Choi also is accused of killing Doo Soo Seo, who also lived in the Tenafly home. He then drove away in Han Il Kim's BMW with at least $30,000 in cash he found in the house, Puccio said.

Choi was treated at a Flushing, N.Y., hospital for cuts he suffered when his victims attempted to fight him off, Puccio said.

On May 6, prosecutors said, Choi left the BMW in long-term parking at Kennedy Airport _ and on May 13, he flew to Los Angeles.

Puccio said that when Choi was arrested in California, he had $88,000 in cash, chips from a casino and credit cards in Han Il Kim's name on him. They also found credit card slips of purchases made in other people's names.

Back in New Jersey, concern was mounting from people unable to reach the Kims and Seo. Finally, on Friday, a relative went to their home and saw one of the bodies.

Authorities found the other two.

Daniel Choi _ no relation to the man charged with the killings -- said he grew concerned after getting a call from Han Il Kim's girlfriend last Friday, asking for help in finding him.

``I thought it was pretty serious, because she never calls me,'' he said.

Choi said Kim -- whom friends called "Sean'' or ``Han Diddy'' because he was a fan of rapper Sean ``P. Diddy'' Combs -- was a close friend and workout buddy and enjoyed going to upscale clubs in New York.

Choi said Kim attended Tenafly High School and got into the cell phone business about six years ago, expanding two stores, both called The Wireless Factory, into a cell phone distribution venture that stretched as far as Philadelphia and Maryland.

No one among Kim's North Jersey friends had ever heard of the man now charged with Kim's murder, Choi said.

Meanwhile, members of the New Jersey Korean Vietnam Veterans Association were mourning the loss of Doo Soo Seo, an active, well-liked member who had fought with the South Korean army in support of American forces in Vietnam.

``He is a very glad and active man -- any kind of event, he always offered assistance,'' said Peter Jung of the association.

All three victims were from South Korea, according to the Korean Consulate in New York. Consulate spokesman Joo Min Lee said Yoo Bok Kim and her son immigrated to America in 1994, and Yoo Bok Kim became a U.S. resident in 2003. Han Il Kim's immigration status was still unclear, Lee said, but Doo Soo Seo received a U.S. green card in 1996.

Puccio said that while questions remain in the whirlwind investigation, the main one is now answered.

``We're convinced that Mr. Choi is the sole actor. In terms of looking for other suspects, the case is closed.''

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