It was an unexpected sight in downtown Patchogue yesterday afternoon.

The Suffolk County Police Emergency Service Unit and officers with long guns were spotted on the roofs of several businesses during the first 'Alive After Five' event of the summer.

At the same time, police said they were conducting an unrelated shooting investigation involving a group of teens half a mile away.

The two incidents, while not connected, raised a lot of community questions about the large-scale police presence in the area.

Today, Suffolk County Police Commissioner Kevin Catalina said he understands the concerns but added the department routinely stations officers with larger weapons on the tops of buildings as part of a larger public safety initiative.

Catalina said thousands of people attended yesterday's event in downtown Patchogue. He added that his department often steps up patrols for events of that size county-wide.

"If you're going to see somebody deployed on a rooftop, they are there to make sure that if God forbid there's an active shooter, that's the quickest way to mitigate that threat," Catalina said. "If there's some kind of other improvised attack, you know again, that vantage point is the best vantage point to have to stop something like that from happening."

As people were filing into downtown, police said a boy, 14, allegedly shot a 17-year-old multiple times, then himself, during a fight that got out of control nearby.

Suffolk County police said the shooting happened around 4:30 p.m. near the intersection of Edwards Street and Rider Avenue.

Police said a 17-year-old was taken to a hospital with serious but non-life-threatening injuries. Officials said the 14-year-old shot himself in the hand and was also taken to a hospital, treated and released.

No one else was injured.

The incident sent additional police to the area, putting more people on edge.

Suffolk County police charged the alleged teen shooter with first degree assault and second degree criminal possession of a weapon.

Catalina said people should expect a similar law enforcement presence, whether they notice it or not, at events all across Suffolk County where lots of people are together.