WASHINGTON (AP) — Amid increasing tensions with Beijing, the Pentagon on Tuesday released a new report that lays out U.S. concerns about China's growing military might, underscoring worries about a possible attack against Taiwan.

Speaking to reporters, a senior defense intelligence official said the key concern is that as China upgrades its military equipment and technology and reforms how it trains and develops troops, it becomes more confident in its ability to wage a regional conflict. And Beijing's leaders have made it clear that reasserting sovereignty over Taiwan is their top priority.

T...