Antero Resources Corp. and its pipeline affiliate agreed to buy natural gas production and pipeline assets from privately-held HG Energy II LLC for a combined $3.9 billion in cash, expanding its reserves of the fuel just as prices are rebounding.

Antero Resources will pay $2.8 billion for upstream assets in the Marcellus shale in West Virginia, it said Monday in a statement. The company also announced the sale of production assets in Ohio’s Utica Shale for $800 million in cash. Bloomberg News earlier reported that the two companies were close to a deal.

Meanwhile, Antero Midstream Corp., a separately listed company, said it will pay $1.1 billion for HG’s pipeline assets.

Denver-based Antero closed trading Friday at $36.75 a share, giving the company a market value of $11.3 billion. Its shares have gained 18% in the past year.

Last week, US natural gas futures hit $5 for the first time in almost three years as cold mid-December forecasts raised demand for the fuel that’s expected to play a large role in the energy landscape amid the artificial intelligence boom.

Antero said in October that it had made three acquisitions worth $260 million in West Virginia.

Founded in 2011 during the early days of the shale boom, HG drills for gas in Ohio, Pennsylvania and in its home state of West Virginia.

HG had explored a potential sale valuing it at more than $3 billion in 2022, Bloomberg News previously reported.