FRANKLIN (CBS) -- The search for a college student who went missing in Franklin over the weekend entered its fifth day Thursday, though he has not yet been found despite the expansive efforts.
Michael Doherty, 20, had just come home on summer break from Duke University, where he is a junior mechanical engineering major. He was last seen leaving a party on Phyllis Lane by himself around 1:30 a.m. Sunday.
He was wearing a blue T-shirt with a Nike logo, black pants, and sneakers. He's white, 5-feet 10-inches tall with brown hair and brown eyes.
In a brief update at 9 a.m. Thursday, Franklin Police Deputy Chief James Mill said the search had covered an area with a radius of over one mile so far.
"Today's search is primarily going to be K9 and water-based," said Mill. "We're going to continue to search in that one-mile radius we spoke of. There are certain areas within that radius that we're going to try to focus on today. They've been very hard to get into, so we're going to try to hit those areas hard with the K9s."
Thursday's ground search was scaled back due to excessive heat.
On Wednesday, Doherty's parents told reporters their son had a planned ride home from the party, but decided to stay a little longer to catch up with friends.
They said he later texted his brothers for a ride home, but they were asleep, so he decided to walk.
"We are devastated, heartbroken, don't wish this on anyone ever, and we just want our son home," Nancy Doherty, his mother, said.
Doherty charged his cell phone a little bit before leaving the home. Police say his phone has shown no activity since then, but marked the spot where they say it was last pinged.
On Thursday, Homeland Security was called in to check Doherty's computer for any signs that he had planned to run away. But the investigation continues to show that Doherty likely went unintentionally missing during his walk home.
Searchers found one of Doherty's shoes and his shirt Sunday in a marshy area. The focus of the investigation shifted to nearby Bellingham after they found his other shoe on the side of a brook there later in the week.
His parents praised the people of Franklin, who were supporting the family and helping with the search.
Police said they do not suspect foul play.
Residents have been donating food, water and coffee for search crews, but police said that while they are thankful for the items, they have plenty of supplies for the time being.
WBZ NewsRadio 1030's Ben Parker reports
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