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Citizen Case Study: Times Square Explosion

12/11/17: New York, New York

Our team at Citizen reviews our emergency response following every major incident covered in the app. We assemble a detailed timeline, evaluate our speed and assess our accuracy. We ask ourselves this question: Is there more we could have done to keep the public safe and informed?

In an effort to further transparency and facilitate an ongoing dialogue with a community dedicated to keeping each other safe, we’re sharing our internal case study on Monday’s attempted terror attack.

First, our timeline: How quickly did Citizen get necessary information into the hands of the public?

7:20am: There’s an explosion near Times Square in the Port Authority Bus Terminal.

7:23:09am: Citizen’s first reporting of the incident appears in the app, generating a notification that reaches 627 users within a 5-block radius of Times Square.

The first two updates are published within seconds:

7:23:26am: “Police are en route to investigate an unconfirmed report of a bomb in the Times Square subway station.”

7:23:35am: “The station is being evacuated.”

For the purpose of this case study, we will not include every update published to the app. See the full transcript here.

7:31:48am: The first Citizen user starts live streaming video from outside the terminal, showing a massive police response and chaos in the streets. Over 7,000 users within a 1-mile radius receive another notification and can instantly watch the situation unfold live.

It has now been 12 minutes since the explosion. First responders are blocking off the perimeter. Flashing lights line the streets of Times Square. And there are reports of shots fired. It’s in these moments that situational awareness matters most. We talk internally about what it would be like in those situations and what questions we’d be asking ourselves: What was that sound? Are people hurt? Am I in danger? What’s happening?

7:32:15am: “There are multiple reports of shots fired coming in at the location; it is unclear if this is from the explosion heard.”

7:32:49am: “Police state one suspect is in custody.”

7:33:44am: “The device that went off is reportedly in a passageway between the (A) and (1) trains.”

7:36:24am: “The suspect in custody possibly has a device and wires on him, according to police; the NYPD Bomb Squad is requested to expedite their response.”

7:44:26am: “The bomb squad is confirming the device.”

7:46:36am: “There is at least one victim from the explosion; the extent of the injuries is unclear.”

7:47:47am: “Police are stopping all trains toward the 42nd St/Port Authority Bus Terminal.”

And finally, after publishing over 70 updates in the span of 3 ½ hours:

9:27:47am: “Police state the bus terminal is almost ready to be repopulated.”

9:55:30am: “Police reaffirm there is no credible ongoing threat.”

During our review, we identified key areas for improvement. Our tech team is working on our notification system so we can send urgent notifications to larger, more targeted areas, or even the whole city. The app froze during peak traffic. We’re reinforcing our system to be able to handle tens of thousands of users without any lag.

We heard from many of you that the information you accessed through Citizen helped you navigate safely, kept you informed, and was available when there was no other information to be found.

“Yesterday morning early into my shift at Central Park (7:20–7:30) I began hearing and seeing a lot of police and helicopters in the area and responding. I knew something was up because the amount of sirens at the time was more than usual. I took a moment to check the app and there the information was. I alerted my co-workers because we work in a place where we know the possibility of such similar incidents is very real. As I began to look deeper into what was going on Citizen had all the info at the perfect time. Thanks to you all at Citizen, I was informed and was ready to make decisions which would impact my safety.”

Citizen user Andre R.

On Twitter:

On Reddit:

We are learning, growing, and remain dedicated to providing real-time information to people when they need to know what’s happening around them. If you’re a Citizen user and were in the Times Square area yesterday, please send us your story at

We at Citizen, along with the rest of NYC and people from coast to coast, are thankful there were no life-threatening injuries reported yesterday. Our thoughts are with the multiple victims and those affected.



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