Fliers were posted all over Boston on Monday as police, family and friends continued to search for a 23-year-old graduate student who vanished without a trace last Tuesday night, NBC station WHDH reported.

Jonathan Dailey, who is in his second year at Boston Architectural College, was last seen inside his apartment.

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"I heard him leave at 9:30 that night, but there was nothing unusual about it," his roommate, Miles Smith, told the Boston Herald.

The next day Smith, who attended Appalachian State College with Dailey, noticed he had left behind his driver's license, computer and clothes. And when didn't show up for work at a Cambridge clothing store on Friday, Smith said he knew something was wrong.

"Jon’s amazingly responsible,” Smith told the Herald.

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“He didn't have his credit card on him, his phone he hasn't contacted anyone. And his debit card was stolen a few days before so no access to money, so it was not like he was going away for a trip on his own,” Veronica Chang, a friend, told WHDH.

His family traveled from North Carolina to join in the search, but so far Dailey has not been sighted.

Boston Police have issued a missing person's alert. Dailey is described as 5-foot-9, weighing about 160 pounds with brown eyes and black hair. Police said he has a black stripe tattoo on his left arm.

A Facebook page was set up by Dailey's friends to raise awareness about his disappearance.

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