CHICAGO (WLS) -- Four men attacked a 54-year-old man leaving him beaten, stabbed and robbed at a CTA Blue Line station in Chicago's Loop, police said.The victim was standing on the platform at the Jackson station in the 300-block of South Dearborn Street around 10 p.m. Tuesday, when police said the four suspects came up and made it clear they planned to rob him.Before they took his cash and ran off, the men started to attack the victim. One of them stabbed the victim in the behind, police said.The victim was taken to Stroger Hospital, where police said his condition stabilized.Police had no one in custody Wednesday.Some commuters felt a little uneasy Wednesday morning after hearing about the attack."The fact that happened literally outside my front door is unnerving," said Jeff Killinger, who lives nearby."There's not enough security over here. You have guys down there, sleeping down there. You have guys doing all types of stuff and there's only a train guy up here. He can't do nothing because he doesn't have a weapon," said Charles Anderson, a CTA rider.It was immediately unclear if the attack was captured on any CTA cameras.