NEW YORK (CBSNewYork) -- Police are searching for a man who they say is robbing passengers riding the southbound L train in Brooklyn.
The first reported incident happened back in February and the three most recent cases all happened April 2 within hours of each other.
Police said the suspect uses a sharp object to cut the front or rear pockets of the riders before swiping cell phones, wallets and bank cards. They said some of his targets are asleep on the train while others are standing or leaning.
News of the robberies left some straphangers on edge.
"Are you kidding me? This is unbelievable," subway rider Derrick Mixson told CBS2's Raegan Medgie.
"Wow, you know, this is New York," said Brownsville resident Charles Wickliffe. "You get all types of crazy people."
"It's really surprising because you know us New Yorkers, we're fast thinkers and we stay alert. I guess this guy's down on his luck," Wickliffe continued. "But he's going to get caught. If he gets caught by the wrong person, he's going to get beat down."
"It's pretty scary," said rider Sharita Davis. "I feel like when you're on the train, you should be aware of your surroundings. I know a lot of times it's easy to want to doze off, but there's people like that on the train."
"Don't fall asleep, make sure you're in a car that has a number of passengers," said Bronx resident Steve Kontonicolaou. "Hopefully this guy makes a mistake and picks on the wrong guy."
"We as customers on the train must be more alert to what's going on," said Brooklyn resident Jones Mare. "And if we do see something, we need to say something."
In total, the suspect struck seven times, Medgie reported. In all of the incidents, the robberies happened between midnight and 5 a.m., and the robber targeted men.
Authorities have yet to identify the suspect but have been stepping up patrols on the subway, specifically utilizing a unit that specializes in pickpockets.
Police describe the suspect as a black man between the ages of 30 and 40, 5'8" to 6' tall and weighing between 180 and 190 pounds. He was seen wearing a light blue button up shirt, black New York hat, blue jeans and black sneakers.
Anyone with information is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS or for Spanish 1-888-57-PISTA (74782), visit www.nypdcrimestoppers.com or text tips to 274637(CRIMES) then enter TIP577.
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