Mystery deepens into disappearance of Brendan Santo as search for Rochester Hills teen enters third week

As the days tick by, the mystery of Brendan Santo's whereabouts has only deepened after his disappearance more than two weeks ago.

The Rochester Hills resident and student at Grand Valley State University was last seen near one of the buildings on Michigan State University's campus the night before the UM-MSU game.

Since then, an $11,000 reward has been posted, tens of thousands of dollars have been poured into a search fund, and students have combined with parents to search for Santo.

"We're just trying to be helpful. We're parents, we have kids in college. We just want to bring Brendan home," said one parent.

On Sunday, volunteers were out looking again. 

Police initially believed Santo hadn't gone too far since his vehicle was found in the same place he first left it. His last known location was outside of Yakeley Hall on Oct. 29. Police believe the Red Cedar River, which meanders through campus, could offer proof about what happened to the teen. 

Over the weekend, hundreds gathered at Santo's alma mater at Rochester Adams High School for a vigil. Family and friends joined and sang, praying for the discovery of the missing 18-year-old.

Search efforts have expanded to include a heavy following on social media, billboards in and around East Lansing, and hundreds of flyers posted around the area.

RELATED: Search for missing Rochester Hills teen continues in East Lansing

Adding to the struggles of searching for Santo is the information that some of the security cameras at Yakeley Hall were not working at the time Santo went missing. That's since been rectified. 

Santo's vanishing has since prompted other law enforcement agencies to get involved, including the FBI and the Michigan State Police Department. 

Find Santo's gofundme here.