<p>A 24-year-old man was critically wounded in a robbery Monday night on the Northwest Side and police have in custody a suspect. </p><p>The victim was outside at about 8:30 p.m. in the 7000 block of West Belmont Avenue when another man approached him, pulled out a gun and demanded his belongings, Chicago police said.</p><p>The gunman fired shots, striking the man in the abdomen, police said.