HOUSTON, Texas (KTRK) -- The woman accused of trying to cover up a Heights-area double murder back in January returned to court on Tuesday morning. Meanwhile, officials believe the men charged with capital murder have fled the country.
Kathy Vu, 23, is charged with tampering with evidence. Previously, a judge in probable cause court set her bond at $40,000.
During her appearance on Tuesday, the court ordered her to surrender her passport and wear an ankle monitoring device.
Investigators say Vu's boyfriend, 26-year-old Polie Phan, and 25-year-old Jaidan Vu Nguyen shot two men to death earlier this year over a narcotics dispute. They are wanted by Houston police.
Officials say Vu purchased cleaning supplies and cleaned up the crime scene. Vu's attorney argues she picked up the supplies under the direction of her boyfriend.
"The two defendants who are currently charged with capital murder, we believe both have fled the country and are living internationally right now," Samantha Knecht with the Harris County District Attorney's Office said.
Vu's attorney, Coby DuBose, specifically said it's believed the two wanted men have fled to Vietnam.
"They think she's going to go flee the country. There's no evidence whatsoever. If she wanted to flee, she could have. She hasn't. She's here," DuBose said. "We're excited, honestly, to get our day in court and see these facts be more developed in a way that I think is fair."
DuBose said he believes Vu and Phan's relationship was relatively new. He said Vu's family just met Phan for the first time around the holidays.
READ MORE: 2 suspects wanted, woman arrested in connection with double murder in Heights area
HPD was called to the 1700 block of West TC Jester on Friday, Jan. 27, about a neighbor being concerned that a Toyota Prius was running inside a garage at about 8:30 a.m.
Dana Ryssdal, 35, was found dead at the home while his friend, 37-year-old James Martin III, was reported missing along with a white Dodge Ram truck that belonged to Ryssdal.
ORIGINAL REPORT: Person found dead after neighbor notices car running unattended at Timbergrove Gardens home
Three days later, on Jan. 30, that truck was found in southeast Houston, but Martin was not located. It wasn't until Feb. 1 that Martin's body was found in the trunk of the Prius at an HPD impound lot, where it was towed for evidence processing. Police said Martin's body was bound with duct tape and had been shot multiple times.
Houston police said an H-E-B receipt from the day of the murders helped lead investigators to Vu.
READ MORE: H-E-B receipt could be key to murders of 2 men in TC Jester home, 1 suspect detained
Police said they found bleach and iodine bottles in the back of Vu's car, and an H-E-B receipt from the day of the murders, showing she bought trash bags, towels, and other items she allegedly used to clean up the crime.
According to documents, the motive behind the murder appears to be drug-related, as police reported finding "marijuana in various places throughout the residence," and bundles of cash totaling $35,980 found in the freezer.
A search warrant says Ryssdal and Martin were in the marijuana harvesting business in Oregon, where it's legal.
RELATED: Missing man's body identified after a friend was found dead in Timbergrove Gardens home, police say
Court documents state that during an interview with Vu, she said Martin had a history of threatening a lot of people, including her boyfriend.
"If anything, because people don't want to pay him back. If anything were to have happened, it would definitely have been self-defense," she told authorities.
She told investigators that Martin owed her boyfriend $40,000 "after a narcotics-related transaction did not go as planned."
However, court documents reveal police believe Martin and Phan had a history and that Phan owed Martin money.
SEE ALSO: Docs reveal marijuana and $35k in cash were found inside home where 2 men were killed on TC Jester
Vu said that on the night of the murders, she had a work-related dinner planned and wanted her boyfriend to go with her, but he did not attend "because emergencies happened." She denied having any knowledge about what happened between her boyfriend and Martin.
However, court documents say Vu was texting and talking with her boyfriend before, during, and after Martin's murder.
RELATED: Man found shot to death in Houston home was visiting from Oregon, police say