A California family that has been missing for nearly two months may have left their San Deigo home and fled to Mexico on their own accord, according to authorities.
"They were making inquiries concerning travel in Mexico and passports which would indicate there was some type of planning ahead that we weren't aware of before today," San Diego Sheriff's Lt. Dennis Brugos told KGTV.
Joseph McStay, 40, and his wife, Summer, 43, disappeared along with their two children, Gianna, 4, and Joseph, 3, from their their serene San Diego-area community in early February.
Brugos said the computer search was done about one week prior to when the family's white 1996 Isuzu Trooper, with the children's carseats still intact, was found near the Mexican border and nearly 80 miles from the family's Fallbrook, Calif., home.
The findings in the family computer support what Brugos has said he already believed: that the family may have crossed into Mexico willingly and were not victims of foul play.
Surveillance footage of a family of four walking over the U.S.-border and into Mexico that fit the description of the San Diego family was recorded on Feb. 8, four days after the family was last heard from.
"We had been somewhat focused on the fact there's a high probablity they had entered Mexico on their own volition and this somewhat reinforces that," Brugos said.
The video was shot at the San Ysidro Port of Entry and, according to San Diego Sgt. Roy Frank's interview with KGTV, the family spotted on the video seemed to be "casually strolling into Mexico" and that each adult was holding hands with one of the toddlers. There was no sign any of the family members were in distress.
Brugos urged the McStay family to contact someone if they are safe and alive.
"Law enforcement has put in a great deal of time and effort trying to locate them and if they could simply contact someone and let us know they're all right that would be a huge relief to a lot of people," said Brugos.
Earlier this month, McStay's brother, Mike McStay, told ABCNews.com that he doubted the family shown on the surveillance tape is his missing relatives. He has also steadfastly argued that his brother and his family would not just pick up and leave without telling him.
"The video quality is very poor. I personally could NOT make a positive identification," Mike McStay wrote on a blog dedicated to his missing family.
"Careful reviews of the video shows that there are two or three different families passing by, one with a little girl actually, and the other with a man who walks nothing like my brother," wrote McStay.
McStay and his father Patrick McStay have disagreed since the family vanished in early February as to whether Joseph McStay might have any reason to travel to Tijuana, the Mexican border town closest the Southern California.
Joseph McStay is the owner of Earth Inspired Products, a company that designs interior decorative fountains, according to its Web site.
His brother said the fountain business shipped worldwide regularly, but he was unsure whether the two young children even had passports.