MINNEAPOLIS — Hundreds of people have gathered at the University of Minnesota to honor a missing student who police believe drowned in the Mississippi River.

A vigil was held Tuesday evening outside the school’s student union for 22-year-old Jennifer Houle. Many of the people in attendance wore purple, Houle’s favorite color, and her Pi Beta Phi sorority sisters released purple balloons into the sky with messages written on them.

Houle went missing early Friday morning after going out to a bar with friends in the Dinkytown neighborhood.

Minneapolis police said Monday that city-owned surveillance video shows Houle entering the river. It’s unclear whether she fell or jumped from a 10-story bridge, but police said she was alone at the time.

Authorities continue to search the river for Houle.