A Lexington man allegedly murdered his wife, then staged her body. Here’s what we know.
Shen Cai, 49, was found dead in an SUV last week. Prosecutors say Hongyan Sun put her body there after a fight.

The day before 49-year-old Shen Cai went missing, she shared a thought with a friend.
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If Cai was ever found dead, “it would be a homicide, not a suicide,” she allegedly said, WBZ-TV reports.
Days later, it was the Lexington mother’s worried friends who found her body inside an SUV early one morning aside a leafy road not far from Lexington High School — a grim end to their search effort.
Now, prosecutors say, they’ve arrested the person responsible. Hongyan Sun, 50, Cai’s husband, is charged with her murder.
During his arraignment in Concord District Court Thursday morning, Sun, who allegedly staged his wife’s body in the Honda CRV on Worthen Road, was ordered held without bail, according to the Middlesex County District Attorney’s Office.
The hearing came amid new details after the discovery of Cai’s body last week stunned the couple’s nearby Baskin Road neighborhood.
“She was a very positive person. I was really shocked,” Weidong Wang, who played on a volleyball team with Cai, told The Lexington Minuteman earlier this week. “I can’t believe this could happen here in Lexington.”
Here’s what we know about the case:
Sun ‘staged’ his wife’s body in her SUV, prosecutors say
Cai was last seen on Tuesday, May 28, according to the district attorney’s office.
Her friends became increasingly concerned about her whereabouts after she missed two scheduled appointments the following day, officials said. She had also told them she worried about her safety, authorities said.
Setting out on a search effort, they found her unresponsive in the driver’s seat of the white CRV around 12:30 a.m. on that Thursday, May 30, and called 911, the district attorney’s office said.
Cai, found with “suspicious trauma” on her body, was pronounced dead at the scene, authorities said at the time.
On Wednesday, the district attorney’s office announced that after an autopsy, the Office of the Chief Medical Examiner had ruled Cai’s death a homicide by mechanical asphyxiation.
“Investigators subsequently learned that Ms. Cai and her husband were in the process of going through a divorce and that she had reported to her friends and her attorney a history of verbal abuse and controlling behavior, as well as one prior instance of physical violence,” officials said in a statement.
The couple allegedly had a physical altercation on the day Cai was last seen alive, according to authorities.
“The investigation suggests that after the struggle in their home, Ms. Cai’s body was allegedly staged and left in her vehicle on Worthen Road in an apparent attempt to mislead law enforcement,” the statement says.
On Thursday, prosecutors detailed the findings, stating that investigators found trauma on Cai’s neck “consistent with being strangled and trauma to her body and extremities consistent with a violent struggle.”
“[Sun] also allegedly had a history of controlling behavior including allegedly using the victim’s immigration status to control her, threatening to not file the paperwork for her to renew her green card if she left him or told anyone what he was doing to her,” the district attorney’s office said in a statement.
The couple was married for approximately four years, although Sun had filed for divorce last September, The Boston Globe reports.
According to court documents filed in October and obtained by the Globe, Cai alleged Sun “sometimes made her and her daughter feel unsafe” and that he frequently verbally and emotionally abused her, along with “other cruelty.”
Sun, who had apparent injuries to his hands and arms, allegedly told police that Cai had bitten his finger during their fight on May 28. He gave conflicting statements about when he last saw his wife, WBZ-TV reports.
Evidence collected at the couple’s house showed someone tried to clean up the crime scene, according to the news station. Sun was also seen throwing away shoes with blood on them at his job, the station reports.
In addition, prosecutors say Sun purchased an upcoming plane ticket to China prior to his arrest, NBC10 Boston reports, and had spied on his wife with hidden cameras in the days leading up to her death.
‘She was a great lady,’ Sun told reporters after his wife’s body was found. ‘That’s it. I’m not going to comment anything at all.’
BREAKING: Hongyan Sun, 50, of Lexington, has been arrested and charged with murder in connection with the death of his wife, Shen Cai, 49. Police say there were signs of a struggle. On Friday, he would not answer when asked him about the injuries to his hands. @7News pic.twitter.com/ZllK4dDG0x
— Alex DiPrato (@AlexDiPrato) June 5, 2019
After the news broke last week that police were investigating Cai’s death, reporters rushed to the couple’s home, a short jaunt from where her body was found.
There, they found Sun, who was returning home in hospital scrubs.
“I can’t tell anything,” Sun told them. “I don’t want to do any more damage to anybody, OK.”
As reporters continued to press for answers, Sun told them he didn’t know what had happened to his wife.
“She was a great lady,” he said, WBZ-TV reports. “That’s it. I’m not going to comment anything at all.”
Asked about the apparent injuries on his hands, Sun said, “It has nothing to do with you, OK?”
Taking a closer look at our Friday interview with Hongyan Sun; he’s now accused of killing his wife.
In divorce records, Shen Cai said she was subjected to “emotional abuse and other cruelty” & there’d been an “irretrievable breakdown of the marriage”. @NBC10Boston @NECN pic.twitter.com/oyGwkordQI— Michael Rosenfield NBC10 Boston (@MikeRNBCBoston) June 6, 2019
Melinda Thompson, Sun’s attorney, told NBC10 Boston Thursday that Sun is trying to make sense of what happened.
Sun is denying the allegations against him, according to WBZ-TV.
“He’s just sort of shocked, and, again, just learning the facts, so we don’t really know where this goes from here,” Thompson said.
Sun is due back in court on July 30.
Churchgoing and talented, Cai moved to the U.S. from China to marry Sun in 2015
About four years ago, Cai uprooted her life in China to get married in the United States, the Globe reports.
At the time, Cai was a marketing director for the food and beverage company Danone in Shanghai, according to the newspaper. She left with her daughter and headed to a future in Massachusetts, where Sun, who has a son, lived in Waltham.
The couple met in 2013 through mutual friends, the Globe reports. Three years later, they bought their Lexington home.
In town, Cai was active at the Chinese Bible Church of Greater Boston, where she was baptized in late 2017, the newspaper says.
On Friday evenings, she met with a fellowship group to study the Bible.
“It’s really very sad news,” Yuegang Zhang, a church minister, told the Globe about her death on Saturday. “It’s really shocking.”
Wang told the Minuteman that Cai’s relatives from China are working to get the necessary visas to come to the U.S. for memorial services.
Those who knew her said Cai was a gifted vocalist, impressing those around her wherever she took to the microphone, whether it was at a karaoke outing or in her church, according to the Globe.
“She’s intelligent, successful, and talented,” Lei Reilley, Cai’s divorce attorney, told the Globe Saturday, days before Sun’s arrest. “This really comes as a shock.”