Brother of reality star Kristin Cavallari missing under 'suspicious' circumstances

Utah law enforcement were still trying to piece together Monday morning what happened to Michael Cavallari. The brother of former MTV reality star Kristin Cavallari and the brother-in-law of NFL quarterback Jay Cutler has been missing for more than week under "suspicious" circumstances.

Grand County Sheriff Steven White told FOX411: “Right now everything is pretty status quo. We are conducting follow ups, and there is not much more to add to that. We are still out talking to people trying to piece things together.”

The Grand County Sheriff's Office said it first became involved in the search for Cavallari, 30, on Nov. 27, when it received a report of an abandoned Honda Civic along Interstate 70 in the southeastern part of the state. Authorities said Cavallari was identified as the car's driver after credit card receipts in the vehicle led them to a convenience store in Monticello, Utah, where they saw him in footage on the store's security system.

The Deseret News reported that Cavallari's laptop and cellphone were found inside the car, which appeared to have hit a large rock on the side of the road. The vehicle's engine was running and its airbag was deployed.

"We're combing the area for anything we can find," White told the paper. "We're deeming it suspicious, but there's nothing to indicate anything one way or another. The vehicle was just abandoned.

Michael Cavallari lives in San Clemente, California. Grand County is about 100 miles north of Monticello and 225 miles south of Salt Lake City.

Michael Cavallari's younger sister, Kristin, rose to fame while still in high school after being cast in MTV's reality series "Laguna Beach". The show aired for three seasons before ending in 2006. Cavallari also made several appearances on the show's spin-off series "The Hills".

Kristin Cavallari married Jay Cutler in November 2013. The couple have three children.

The Associated Press contributed to this report.

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