A man wearing body armor and carrying a gun was arrested while walking on a helicopter pad at Boston Medical Center on Saturday, according to Boston police.

Boston University police and Boston police made the arrest at 4:25 p.m. at 720 Albany St., according to Boston police spokeswoman Rachel McGuire. The helicopter pad is at ground level.

Colin Riley, a spokeman for Boston University, said that the helicopter pad is adjacent to the Boston University Medical Campus, but is part of Boston Medical Center.