NEW HAVEN, Conn. (WTNH) — On the street, they’re known as “ghost guns” and law enforcement is seeing them more and more across the country and the state.

“Ghost Gun is a slang term,” explained Scott Riordan, resident agent in charge for the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF). “We refer to them as ‘self-made, unserialized firearms.’”

Whatever you call them, they were outlawed in Connecticut in 2019. But now, they’re popping up across the country. Including Connecticut.

Ghost guns are assembled from kits that are sold without background checks and can be purchased online and at gun shows. It’s easy for those who otherwise would not be allowed to possess a firearm to acquire one.

“We are seeing them become more prevalent out on the street,” said Captain John Healy of the New Haven Police Department. “Likely being used in crimes of violence.”

Typically, the guns start as 80% receiver, or frame, which houses other parts. The guns are relatively cheap to make and easy to mass-produce. Federal law allows a private individual to make a firearm for personal use. Even though they were outlawed in Connecticut, they are still ending up in the wrong hands.

“It’s important to realize that when ATF gets involved in these cases it’s most likely for other reasons such as prohibited people in possession of these firearms, people who are not allowed to possess firearms,” Riordan said.

“The problem with the ghost guns, obviously, is they’re unregulated,” said Healy. “They’re unserialized and therefore…very difficult to trace. Almost untraceable without the serial number.”

In addition to his shooting task force, Healy is working with the ATF to get these firearms off the streets. He said on Wednesday New Haven Police recovered their tenth ghost gun this year. Last year the department recovered three.