Police in Corpus Christi, Texas are continuing their search for missing college student Caleb Harris a week after he suddenly vanished. 

The 21-year-old Texas A&M University-Corpus Christi student reportedly disappeared after ordering a food order from UberEats in the overnight hours on March 4.

Police say he was last seen outside of his apartment around 3 a.m. They say Caleb left behind his keys, vehicle, and wallet. He did have his phone with him but is now turned off, they noted.

His roommates were unable to locate him later in the morning and then his family reported him as missing.

His parents told Fox News that they received Snapchats from Caleb at about 2:45 a.m. when he went to take his new dog for a walk. The family then says that he put the dog back inside the apartment and went outside to wait for the Uber Eats order.

The order was marked as completed, his family said.

Retired FBI agent Jennifer Coffindaffer, who acts as an expert witness in criminal cases and is a law and justice contributor for NewsNation says the story surrounding the disappearance keeps changing.

 Her theory is that "he met with someone and left and something unexpected happened."

Caleb is approximately 5'11" and weighs about 180 pounds. He has brown hair and brown eyes.

An ongoing search for Caleb includes the East and South parts of North Padre, including behind the apartment complex where he lives. Hundreds of volunteers are also taking part in the search, WOAI-TV reported.

If you have any information that may assist Investigators or know the whereabouts of Caleb Harris, please call the Corpus Christi Police Department directly by calling (361) 886-2840 or by calling (361) 886-2600.

Friends have set up a fundraising account to help the family with expenses as the search continues. It has raised nearly $50,000.