We've been receiving reports from tipsters and seeing chatter on Twitter that there is a possible hostage situation, involving a gunman, happening right now on 22nd Street near the Flatiron building. According to tipsters in the area, cops have blocked off a four-block area on Broadway, north of 21st and south of 23rd, south of Madison Square Park. One person told us that "everyone is looking out the window at 21st and Broadway...and there are people with binoculars on the roofs." We'll update as we learn more about the situation; you can send us info at tips@gothamist.com.

Update: according to several Twitterers on the scene, there is a man with a gun holding his wife hostage. In addition, cops are advising people in the Flatiron building to stay away from the windows.

Update [3:26]: other Twitterists are reporting that there may have been shots fired already, although another advises: "ok, ok, let's all keep calm. gunman in flatiron area appears to have locked himself into an apartment." The NY Observer is reporting that the incident appears to be taking place at the Argo Tea shop in the retail space at the bottom of 949 Broadway, between 22nd and 23rd Street.

Update [3:38]: a worker inside the Flatiron building notes that the hostage situation is happening at the building next to the Flatiron: "Please note, no has barricaded themselves inside the flatiron. We are all safe. It is in a nearby building." Others are confirming that it isn't at the Argo Tea Shop as was previously said, and WNYC reports: "NYPD confirm someone has barricaded themselves in an apt near (not at) the #Flatiron building, and officers have responded."

Update [3:44]: a reader sent in the three photos above, and wrote: "These were taken at 2pm today outside the Polaris nail salon on 22nd east of Broadway. The police entered the building next door." To be clear: the hostage situation is not taking place at the Flatiron building. According to a source there, "the police said there have been no shots fired and it's taking place at 14 E.22nd street."

Update [3:50]: conflicting reports coming in. One reader says he talked to a cop on the scene, who told him: "The guy shot his landlord, people saw through the window, now he's barricaded himself in his apartment. Apparently the NYPDs got snipers on the scene."

Another Twitterer is writing that police "took down police tape on broadway between 22 and 23 outside the flatiron", and that ambulances are making their way to the scene.

Update [3:55]: WNYC reports: "A person barricaded himself inside an apartment near the Flatiron building after contractors working on windows at the location called police because they were being "menaced" by a tenant who may have a gun, police said." Reports are coming in that a man has been led away in handcuffs by police...and the gunman was reportedly wearing Daisy Dukes.

Update [4:04]: Police have now confirmed to us that they have the suspect in custody, there were no injuries, and no shots were fired.

The Daily News adds this tidbit: the man is believed to be in his 70s, and was taken to Bellevue Hospital.