Indiana University student Lauren Spierer missing since Friday

(CBS/AP/WISH) BLOOMINGTON, Ind. - Police are searching for 20-year-old Indiana University student Lauren Spierer, who was last seen heading back alone to her apartment Friday, walking barefoot after a night out with friends.

Witnesses saw Spierer walking toward her apartment building around 4:30 a.m., reports CBS affiliate WISH. Police say surveillance video shows that the student never arrived at her apartment building after parting with friends.

Police, including canine units, have made several searches of the area where the 20-year-old disappeared, reports WISH.

Over the weekend Spierer's parents arrived in Bloomington to help search nearby wooded areas, lakes and construction sites. Family tells WISH that the student has a heart condition and requires medication.

Spierer is described as a white woman, with longer than shoulder length blonde hair, blue eyes, and a slender build. She is 4-feet-11-inches tall. She was last seen barefoot, wearing a white tank top with a loose light-colored shirt over it, and black full length stretch pants.

Anyone with information is asked to call the Bloomington police department at 812-339-4477.