(Reuters) -Defense technology startup Epirus has raised $250 million in a Series D funding round, as it looks to scale up production of its anti-drone weapons, the company said on Wednesday.

Epirus did not disclose its valuation for this round. The company was previously valued at $1.35 billion when it raised $200 million in Series C funding.

The cash infusion comes at a time when defense contractors are straining to meet the surge of demand for weapons following Russia's invasion of Ukraine about three years ago. Epirus won a $66 million contract in 2023 to supply its flagship product Leonidas to the U.S. Army.

Torrance, California-based Epirus is among several aerospace companies that develop weapons which can destroy unmanned aerial vehicles using lasers or microwaves.

The round, which was oversubscribed, was co-led by venture capital firm 8VC and Washington Harbour Partners LP, a D.C.-based investment firm. U.S. defense giant General Dynamics' tank manufacturing unit, General Dynamics Land Systems, also participated.

The latest round, which was oversubscribed, brought Epirus' total funding to over $550 million.

Epirus intends to use the new funds to expand into international and commercial markets, strengthen its supply chain, and grow its workforce. The company is also set to open a new simulation center in Oklahoma to train soldiers in counter-drone warfare.