Tons of Helicoptors, fire trucks, police on Fulton Ave this morning

Anyone know what happened?

This morning I was on Classon Ave and Fulton Street, and for about a half hour I saw more and more fire trucks, ambulances, and police cars than I've ever seen in one place since 9/11 keep arriving. There were also several helicoptors flying over the area. 

Anyone know what happened?

Might match this event this morning:

U/D Brooklyn: Box 3945 at Fulton St & Downing St FDNY on scene reporting a person down an elevator shaft approx 20 feet.

https://twitter.com/NYScanner/status/667017083021041664

Thanks WhyNot.