Christian Aguilar Missing: Authorities continue to search for University of Florida student

(CBS) MIAMI - Family and friends of Christian Aguilar, an 18-year-old University of Florida student who went missing last Thursday, resumed their search for him on Monday, CBS Miami reports.

Pictures: University of Florida student missing

Aguilar was last seen on Thursday, September 20, 2012 at 6 p.m., when he reportedly got into a fight with 18-year-old Pedro Bravo. Bravo is Aguilar's high school friend who used to date his current girlfriend, according to Christian's father, Carlos Aguilar.  Aguilar did not say if he thought the fight may have been over her .

Bravo reportedly told police that he left Aguilar in a parking lot in northwestern Gainesville after the fight. Police believe that Aguilar may be disoriented, seriously injured, and unable to seek medical attention.

Although Bravo has not been charged with a crime, he is considered a person of interest in Aguilar's disappearance. He was, however, held for mental examination after he allegedly made comments to investigators that he wanted to harm or kill himself.

Aguilar is a freshman at the University of Florida majoring in biomedical engineering and is reported to have a history of depression.

The Gainesville Police Department and the University of Florida Police Department began their search for Aguilar on Friday.

Carlos Aguilar and the rest of his family have also assisted in searching the woods, "I cannot do it by myself, even though I'm gonna try," said Aguilar.