Oxford Networks, the Lewiston-based telecommunications company, has merged with a New York company following its acquisition by an investment group.

The merger, which closed Tuesday but was originally announced in July, creates a 5,000-mile fiber optic network that reaches into Maine, Vermont, Massachusetts, New Hampshire and New York, according to a release announcing the deal. Financial terms were not disclosed.

Oak Hill Capital Partners, an investment group based in Texas, has combined the operations of Oxford with FirstLight Fiber, based in Albany, New York. Novacap and Bank Street Capital Partners, which bought Oxford Networks in 2014, will continue as minority investors in the combined company.

“Serving our customers has always been our main priority, and we are confident that combined with FirstLight, we are better positioned to continue to do so,” said Craig Gunderson, president and CEO of Oxford, in the release. “We look forward to working together to realize the promise that this combination creates.”

Oak Hill intends to acquire another telecommunications company in 2017, Sovernet Communications in Vermont, that will also merge into FirstLight, culminating in a network spanning 9,500 route miles in five states and Canada, more than 5,000 on-net locations, and 11 data centers with 128,000 square feet of space.

Oxford Networks, whose roots extend to 1900 when it was founded as Oxford County Telephone & Telegraph Co., employs about 120 people.