CHICAGO (WLS) -- Authorities are asking for the public's help to find the possible serial robber responsible for attacking several men in downtown Chicago and on the city's Near North Side.
"This offender is known not only to Chicago police, but is known to front desk clerks and hotel staff all throughout the downtown area," said Ald. Brian Hopkins, 2nd Ward. "We believe he's been doing this for a while."
On Friday, Chicago police issued a community alert warning of the danger.
There have been at least four attacks, of which the most recent occurred Tuesday night when investigators say a man arranged to meet someone at 900 North Michigan Avenue before becoming the victim of a stun gun attack and robbery.
Detectives say that man met his attacker on Grindr, a well-known dating and hookup online app for gay and bi-sexual men.
The incident follows a trio of attacks which began last month. The first known attack was on December 22nd along the Ohio Street corridor. About two weeks later, on January 6, the robber struck again near Randolph and Dearborn. There was another attack on on January 23 in the 600-block of North Lake Shore Drive at the W Hotel.
Authorities say that's where a 42-year-old man told police he was robbed inside a hotel room by an offender using a Taser after using a dating app to meet a person there.
As Chicago police warn of the extreme danger, so is Steve Bernas of the Better Business Bureau, who says precautions should always be taken.
"Romance scams is one of the top scams at the Better Business Bureau," Bernas said. "They look at separating you from your money, and sometimes they can harm you and sometimes you can get into trouble."
Police say it appears there is only one suspect for these four attacks, but there could be other suspects responsible for other attacks that may have gone unreported. They are following all of those leads.
No one is in custody. Anyone with information is asked to contact Area Central Detectives at (312) 747-8380.
Chicago police warn of robber using dating app to lure victims in Loop, Streeterville