Russian Buildup Stokes Worries

Pentagon Alarmed as Troops Mass Near Ukraine Border.

Russian troops massing near Ukraine are actively concealing their positions and establishing supply lines that could be used in a prolonged deployment, ratcheting up concerns that Moscow is preparing for another major incursion and not conducting exercises as it claims, U.S. officials said.

Such an incursion could take place without warning because Russia has already deployed the array of military forces needed for such an operation, say officials briefed on the latest U.S. intelligence.

The rapid speed of the Russian military buildup and efforts to camouflage the forces and equipment have stoked U.S. fears, in part because American intelligence agencies have struggled to assess Russian President Vladimir Putin’s specific intentions.

The troop movements and the concealment—involving covering up equipment along the border—suggest Mr. Putin is positioning forces in the event he decides to quickly expand his takeover of the Crimea peninsula by seizing more Ukrainian territory, despite Western threats of tighter sanctions.

Still unknown, however, is Mr. Putin’s plan, or whether he has one.

The Kremlin has defended the deployments as a legitimate military exercise on Russian soil.

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