Prior to the power outage, police responded to reports of an explosion at the substation and officers at the scene observed Con Edison workers addressing the transmission line issue. 

"Last night, just before midnight, a piece of high voltage electric equipment failed in the substation, basically a short circuited that caused a large flash that was seen by some residents around the neighborhood, the protection which are basically breakers or like the circuit breakers in your house, just much bigger, they opened up the isolate that piece of equipment, there was a voltage dip, essentially, people saw a flicker in their lights for about a second a little bit before midnight, and then voltage recovered or kind of went back to normal," Con Edison President Matt Ketschke said in a statement early Friday.

The momentary outage resulted in various disturbances across the five boroughs, with the FDNY responding to several incidents of people trapped in elevators. 

The MTA noted that all elevators and escalators at Grand Central were out of service for a brief period following the outage. However, most train lines were still running close to or on schedule. 

No injuries were reported as a result of the incident, “especially to ConEd employees who arrived and responded to the scene,” an NYPD spokesperson said in a statement. 

There were also no reported disruptions to any critical care facilities in the city, such as hospitals, the spokesperson added. 

Police said no criminality is suspected.