A 40-year-old Portland man accused of murdering his domestic partner is claiming self defense in her shooting death, saying she had a knife when he shot her, a detective testified in court Friday.

But investigators and prosecutors said Anthony Leng’s version of events shifted over time, and they believe he killed Sohka Khuon, 36, because she was angry at him for having an affair with a coworker. Police believe Leng altered the scene after her death to make it appear that he acted in self defense.

Police responded to the Riverton neighborhood home the couple shared with two of their three children after 10 p.m. on Jan. 7 and found Khuon on the kitchen floor, Detective Lisa Sweatt of the Portland Police Department testified Friday. Khuon was shot at least five times in the head and neck, and was slumped against the dishwasher with a kitchen knife resting on the palm of one hand and eight other knives scattered around her, Sweatt said.

Khuon was apparently shot moments after returning home. She was still wearing her winter coat and had her purse around one arm. Underneath the body, police found her house keys.

The details emerged Friday at a probable cause hearing where the state’s prosecutor, Assistant Attorney General Meg Elam, had to prove before a judge that police had enough evidence to charge Leng with Khuon’s murder. Justice Andrew Horton found that probable cause existed, and ordered Leng held without bail.

POLICE DESCRIBE THE EVIDENCE

Leng’s attorney, Peter Cyr, argued that Leng acted in self defense, and that the state had not met its burden to prove Leng should be charged criminally. He also sought bail for Leng, saying he has been cooperative throughout the investigation, has deep ties to the community and would not flee or attempt to disrupt the judicial process. A neighbor said the couple had been together since attending the same high school in Portland.

Leng did not speak during the hearing, but sat between his two attorneys and occasionally wiped tears from his eyes. Several relatives were seated behind him in the last two rows of the courtroom.

In addition to new details about what police think occurred that night, testimony by Sweatt revealed why it took investigators several days to clear the scene at 46 Dorothy St. After collecting evidence immediately following the death, investigators returned to the home Jan. 11 accompanied by Leng, his attorney and a prosecutor to walk through what Leng said happened.

According to Sweatt, Leng told them that the couple had spent the evening at a friend’s house watching football, but got into an argument on the way home. Sweatt said Leng heard Khuon tell him to leave the house. Leng told police that he was putting his loaded Glock 30 handgun in a safe in the bedroom when he turned around to see Khuon with a knife in her hand. He told police that he fired the gun at her because he became fearful during the confrontation and went into “defense mode.”

But police said Leng’s version of what happened did not comport with the evidence at the scene, and that Leng’s story changed over the course of the investigation, from Khuon reaching for a knife, to Khuon lunging at him with a knife.

Leng’s account of what Khuon said to him before the shooting also changed, Sweatt said. Although he first recalled her telling him to leave the home, at the second meeting with police, he described Khuon as mumbling.

Sweatt, citing a report by the Medical Examiner’s Office and evidence collected from the scene, described evidence that appeared to debunk the self-defense theory. She said technicians found bullet holes in the cabinet about 6½ inches from the floor, and that pieces of wooden debris from bullets striking the cabinet had fallen onto Khuon, indicating that she was already on the ground when some of the rounds were fired.

A total of 10 shell casings were recovered. Khuon was shot five times, and police found eight bullets or bullet fragments in the home and in Khuon’s body.

Questions also were raised about the knives. Some of the cooking knives that were scattered around her were laying on top of Khuon’s hair, meaning she was on the ground before the knife came to rest there, Sweatt said.

THREE CALLS TO 911

In the house at the time were the couple’s two sons, aged 15 and 10. Sweatt said of the three 911 calls that night, the first came from Leng, who gave his home address but said little else. Another came from a neighbor who reported hearing one gunshot, followed by a succession of others. The third call came from the couple’s 15-year-old son, who told a dispatcher that his father shot his mother.

It was unclear if the boy witnessed the shooting, or saw the aftermath.

Leng also changed his story when asked about whether he knew the children were home at the time of the shooting. At first he said he knew they were in the house, but later said he did not know.

When police arrived, Leng came out of the home and was quickly detained by officers and interviewed at the police station on and off for the next nine hours. They found the handgun in the kitchen, its slide in the back locked position, and a manually operated red-dot laser sight still switched on.

Leng cooperated with the police investigation for several days, Sweatt said. He was arrested nearly a week later after an officer asked him to come to the police station to retrieve his truck keys. Police were afraid he might harm himself, his children or that he would flee, Sweatt said.

Part of the police investigation also involved an alleged affair Leng was having with a coworker. Prosecutors say they believe that Leng actually shot Khuon because she was angry at him for having the affair. Although the coworker had filed a harassment complaint against Leng through their employer, she still described Leng as a friend and the two saw each other at the woman’s home the day before Leng allegedly shot Khuon.

When police first arrived at the family’s home at about 10 p.m. that night, they found two of the couple’s children outside.

A third child, age 18, was not living at home when the shooting occurred, neighbors said. Sweatt also described previous instances of troubling behavior by Leng.

CHILDREN DESCRIBED THREATS

The couple’s children told police their father had threatened to kill their mother in the past, and also threatened to kill himself, Sweatt said. Once, Leng said he was going to shoot Khuon, and went out to his truck where he kept a gun, Sweatt said. But instead of returning with the weapon, he drove off.

The 18-year-old daughter also told police that Leng once told her to kill herself. Khuon had also described Leng’s threats in a text message to her brother.

Khuon, a native of Thailand and a 2000 graduate of Portland High School, worked at Direct Mail Maine in Scarborough.

Khuon’s family has declined to comment on her death but described her in an obituary as sweet and outgoing with a great sense of humor. She liked to spend time with her children, friends and family, as well as to garden, fish and cook new recipes, the family wrote.

Leng, a maintenance worker for the Portland Housing Authority since 2006, was known among neighbors as a family-oriented man who went out of his way to help others.

Police said Leng has no history of criminal convictions. He was known by neighbors to be a hunter and sportsman, and owned firearms and hunting bows, neighbors said.

Following the shooting, the Department of Health and Human Services issued an order that he not have contact with his children. Police said Leng violated the order from jail, when he asked a relative to put his 10-year-old son on the phone.

Matt Byrne can be contacted at 791-6303 or at:

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