Three missing North Texas children were found alive Thursday night, locked inside their parked SUV with their deceased mother, outside a McKinney shopping center.[[374216361,R]]

Police said Christine Thi Woo was found dead in her 2011 Honda Pilot about 6:30 p.m. in the parking lot of the Target store on the 8900 block of Texas 121 at Custer Road.

Woo's cause of death is unknown and will be determined by the Dallas County medical examiner.

The children, 1-year-old Leah Woo, 3-year-old Nathan Woo and 5-year-old Lauren Woo, were found alive in the vehicle, police said, and appeared to be OK but were transported to an area hospital for evaluation.

Three missing North Texas children were found alive Thursday night, locked inside their parked SUV with their deceased mother, outside a McKinney shopping center.

The children's father, Brandon Woo, went to the hospital to be with them, police said. On Friday, he issued the following statement: “Thank you for your thoughts and concern for the wellbeing of my family. We request that everyone please respect our privacy as we focus on healing.”

The family's church, Stonebriar Community Church, said the children are at Children's Medical Center in Dallas.

"We’re doing all we know how to do right now," said Carol Spencer, church spokesperson and senior director of ministries. "A lot of praryer, tons of prayer for this family. Such a sad situation for all of us our hearts are just broken."

Video of Christine Woo and her children at a local store on Monday. Call us at 972-292-6010 if you have information. pic.twitter.com/FLISOIvhsg — Frisco Police (@FriscoPD) March 31, 2016

Spencer said the family has attended the church for the last four or five weeks and that the children have been attending Sunday school. She said church representatives are with the family at the hospital to assist in whatever way they can.

Police are investigating after the body of Christine Thi Woo was discovered in her vehicle near a Target store in McKinney. Her three young children were alive inside the vehicle.

"I wish we had an answer," Spencer said. "We know nothing. We’re all just as baffled as everyone else is. It's just a sad, sad situation and it just breaks our hearts"

A Frisco police spokesman, Sgt. Jeff Inmon, declined to speculate about the woman's cause of death.

"At this point we're conducting an investigation to determine exactly what happened," he said. "The medical examiner's office, however, will determine the cause of death. We're all saddened by this incident and it's unfortunate but hopefully it'll bring some closure to the family."

On Friday, Frisco police said it had no update on the case and that it may be at least a week before any new information is available. The Collin County Medical Examiner's Office said it had no information on Woo's death as of Friday morning.

The three young children of a Frisco woman whose body was found in her vehicle at a McKinney parking lot were rushed to a nearby hospital Thursday.

Christine Woo and her children were last seen in Frisco Monday morning. Police tracked her last credit card to purchases at a Frisco Walgreens and McDonald's Monday between about 10 a.m. and noon.

Police continue to investigate at the scene, and additional details have not yet been released.

Husband Speaks to NBC 5

Brandon Woo, told NBC 5 Thursday that he texted his wife on his way home from work Monday and didn't get a response. When he arrived home they were gone.

"Got to the house, no kids, no wife, so I'm thinking, 'OK they may be out at the playground, shopping, somewhere,' so I give her a call. Cell phone rings in the other room," Brandon Woo said. "She doesn't have her cell phone, can't track her from her cell phone."

"Started getting worried when it got to 8 o'clock, now nothing. Nine o'clock, 10 o'clock, stayed up all night of course, worrying," he said.

Frisco police say a mother not seen since Monday has been found dead in McKinney, and her three children are alive.

Brandon Woo said he returned to work Tuesday morning, but would later tell his boss his family was missing and was allowed to return home.

"I know a lot of your viewers are asking me why did you wait so long to file a missing person report," he said. "Call it ignorance. I always thought that you had to wait 24 hours for a person to be missing before you can file a report. Once I did file a report on Tuesday evening, the police obviously educated me on that, saying, 'No you don't have to wait.' As soon as you think they're missing you can file a report, doesn't matter how long."

Brandon Woo said there was no further activity on the couple's credit cards, or even their Toll Tag, beyond Monday morning.

It is not clear how long the SUV had been in the Target parking lot.

Vigil for Woo Family

Friday evening, a few dozen people gathered at a vigil at Warren Sports Complex.

They lit candles and prayed for the Woo family.

"I don't know what happened that day but I know that three children lost their mother," said Cate Biggs, founder of Frisco Moms Care, which organized the vigil.

"That breaks our hearts," Biggs said.

NBC 5's Chris Van Horne and Scott Gordon contributed to this report.