A submarine arms race is intensifying as China embarks on the production of a new generation of nuclear-armed submarines that for the first time are expected to pose a challenge to growing U.S. and allied efforts to track them.

Analysts and regional defense attaches say evidence is mounting that China is on track to have its Type 096 ballistic missile submarine operational before the end of the decade, with breakthroughs in its quietness aided in part by Russian technology.

Research discussed at a conference in May at the U.S. Naval War College and published in August by the college's China Maritime Studies Institute predicts the new vessels will be far harder to keep tabs on. That conclusion is credible, according to seven analysts and three Asia-based military attaches.