An expansive search that involved a Maine Warden Service helicopter and scores of family and friends failed to find a Freeport guitarist missing since Saturday night when his band was scheduled to perform at an outdoor gathering in Howland.

Dean Levasseur, 24, disappeared about a half hour before his band, Roots, Rhythm & Dub, was scheduled to go on stage at Chickenfest, a bash organized each year by students at the University of Maine.

Levasseur is a dedicated band member and unlikely to skip a gig, friends said. He also left his guitar at the stage.

“He’s a very bright, friendly guy. I don’t think I’ve ever seen him with a frown on his face,” said Deanna Jordan, who is friends with Levasseur’s sister and has known him for years. “I know that he’s very passionate about his music and the fact that he didn’t show up to play Saturday night is very disconcerting.”

Concern for the Caribou High School graduate prompted friends to drive two hours from Aroostook County, as well as others from Bangor and points south, to join in the search.

“He’s a bright, intelligent young man,” said Kyle Anderson, a high school friend who came from New Sweden to join the search. “He has a lot of potential. All and all, he’s a great guy.”

Chickenfest is an unauthorized gathering put on each year by UMaine students at different locations in the Bangor area. The spot in Howland, on paper company land, is predominantly dense forest and bogs, with a small clearing where many students — numbering between 200 and 400 — gathered for the evening concert and barbecue.

Levasseur was last seen shortly before his band was scheduled to perform at 11 p.m. He did not show up for the performance and he failed to respond to an announcement made over the public address system, according to the state police, which is heading up the search. The band played the set without him, authorities said.

“He’s an awfully nice guy, a really optimistic, upbeat person,” said Brendan Parsons, who plays piano and sometimes sits in with the band. “It’s just kind of uncharacteristic like for Dean to not be in touch with anybody.”

Parsons described Levasseur as laid back, thoughtful and optimistic, “just chill and like he’s always listening.” Levasseur has played with the band — based in South Berwick — for a couple years, performing reggae covers and the band’s own music.

Parsons said he attended Chickenfest. Bands started at 7 p.m. and a DJ played in between sets.

“This was just on a logging road. It wasn’t a huge field, kind of compact, a couple hundred people,” he said. “Good times, no violence or anything. Just college kids and music and fires.”

Anderson said some 55 to 60 people had shown up to search by midday Tuesday and others kept coming in the afternoon. It was difficult terrain.

“It is really thick woods, a lot of swampy areas, full of thick brush,” he said. He said the area looked like it might have been an old logging site years ago. Authorities said the search covered roadsides and the area near the party site, but turned up no clues. They plan to resume after 7 a.m. today

Although he is from Caribou and his driver’s license lists an address in Bangor, authorities said Levasseur has been living with his mother in Freeport. His LinkedIn social networking page said he has been attending Southern Maine Community College. He attended New England School of Communications in Bangor from 2008-2010, the page says.

Levasseur’s older sister, Deidra, recruited search volunteers through a Facebook website “Search for Dean Levasseur.” At one point, more than 130 people had pledged to join the effort. The search is covering a large area.

Levasseur’s cellphone signal was last identified Monday morning from a tower in neighboring LaGrange, though police said the phone could have been anywhere within a 10-mile radius of that location.

Friends are hoping for the best.

“I hope and pray that they’re able to find him soon, safe and sound,” Jordan said.