Foreign threats to the US election are on the rise, and officials are moving faster to expose them

WASHINGTON (AP) — A presidential candidate's phone is hacked. A fake video falsely shows ballots burned in Pennsylvania. National security officials warn that U.S. adversaries may incite violent protests after Election Day.

These developments — all revealed in the past week — show how Russia, China and Iran have increased the pace of efforts to meddle in American politics ahead of next month's election, just as intelligence officials and security analysts had predicted.

At the same time, officials, tech companies and private researchers have adopted a more aggressive defense by swiftly exposin...