Video shows people climbing into a Queens manhole in 3rd recent incident

A mystery is deepening underground in New York City.

For the third time in just a few days, there has been an incident of unidentified individuals climbing into manholes to enter the city's sewer system. All of the incidents were captured on surveillance video. 

"That was a first"

The first two took place in Brooklyn. The third was reported in Queens. It took place at around 2 a.m. on May 5 on 250th Avenue in Astoria.

Surveillance video shows three men casually approaching a city manhole. One of them is seen removing the cover, and then they are seen entering the sewer, assisted with a spotlight from a nearby idling car, waiting for them to go underground.

"I was born and raised in Astoria, Queens, you know. I've seen a lot of crazy stuff happen, but that was a first," witness Aki Jakapovic said.

Jakapovic watched as he worked late at his autobody shop nearby.

"We glanced at each other real fast, but I didn't know what was going on. They started doing what they had to do. They picked up the manhole. They all went in and covered it. You know, very suspicious," Jakapovic said. 

"Who's going to go in a manhole to be a scavenger?"

Jakapovic said he call 911, but never heard anything come from the incident. Recent incidents of unknown individuals entering manholes in Brooklyn last week compelled him to come forward.

"I was like, oh my God, this actually happened to me. You know, I saw a lot of views and a lot of people looking at it, and everybody suspicious. Like, what's going on?" he said.

That's the question everyone has.

The NYPD says while it is actively looking into these incidents, it insists there is no active threat to public safety.

Sources tell CBS News New York new intelligence suggests individuals involved at least in the two Brooklyn cases may have been "treasure hunters" looking for valuables tossed in the sewer system.

"You know, who's going to go in a manhole to be a scavenger? What are you really going to find?" area resident Bryan Garcia said. "It's concerning and crazy for a lot of people."

There have been no arrests made in the cases.