Groton – An investigation by city police detectives has led to the arrest of an Electric Boat employee for allegedly making a “credible threat” against the lives of specific EB employees at the submarine maker’s facility at 75 Eastern Point Road.

Edward Lesniak, 39, of Coventry, R.I., faces charges of first-degree threatening and breach of peace for a threat police said he made on Friday. Lesniak, who works overseas, was detained at John F. Kennedy International Airport in New York on his way back into the country on Saturday.

He was arrested by federal customs agents, turned over to New York Port Authority Police and charged as a fugitive from justice.

Coventry, R.I., police assisted City of Groton police by seizing weapons at Lesniak’s home. Those weapons included a .50 caliber rifle, a shotgun and multiple handguns. Police did not indicate if he legally owned the guns.

City of Groton police said in a statement Monday afternoon that Lesniak remains in New York awaiting extradition to face charges in Connecticut. Police did not release details of the threat and were not immediately available to comment. First-degree threatening is a felony.

Police said the investigation is ongoing but “appears to be an isolated incident,” with no other arrests anticipated. The timeline for Lesniak’s extradition back to Connecticut is unclear. He faces a $200,000 bond on the Connecticut charges.

An EB spokesperson was not immediately available to comment on the charges Monday.

 - Greg Smith