BOSTON (CBS) – Friends of Michael Kelleher are hanging fliers around the area of TD Garden, desperately hoping someone will recognize the 23-year-old who went missing Wednesday night. He was last seen at a Celtics game with a co-worker.

His mother Lori is trying every avenue to find him with a helpless feeling. “I went back to the Garden, up and down alleys, showing pictures in bars and restaurants, anything I can think of. I don’t know what to do,” she tells WBZ-TV.

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Michael Kelleher. (Courtesy Photo)

His family says Michael left the game early, but told his friend he’d later meet her at the car, though he never showed up. The last ping on his cellphone was between 10 and 11 p.m. on Tremont Steet, a mile away.

State Police also say his Uber account shows he tried to hire an Uber car in the area behind the Garden that night. His sister Jessalyn says everything since has gone silent. “This is not like him not to talk to anyone,” she says. “He hasn’t used his credit or debit cards, we don’t know where he is.”

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Surveillance image of Michael Kelleher (Image from BPD)

Their panic is growing by the minute saying Michael knows the Garden area, but not his way around the city. In identifying him, they point to distinctive tattoos on his left arm including one of a skyline.

But the family admits right now they have few clues to go on. “There’s no trace, I don’t know what happened,” said Lori Kelleher.

They’re doing all they can through social media and with their own missing person campaign hoping someone will notice something.

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“You want to do something but you don’t know what to do,” said Jessalyn Kelleher. “Is it better to stay in one spot or keep looking, we’re not sure right now.”