The United States on Thursday accused Russia of firing artillery across the border to attack Ukrainian military positions.
"We have new evidence that the Russians intend to deliver heavier and more powerful, multiple rocket launchers to the separatist forces in Ukraine. And we have evidence that Russia is firing artillery from within Russia to attack Ukrainian military positions," State Department spokeswoman Marie Harf told a regular briefing.
Harf said the evidence was based intelligence information but declined to elaborate.
The United States on Wednesday blamed Russian President Vladimir Putin for being responsible for the downing of a Malaysian airliner that killed 298 people on board.
Washington has also urged Moscow to ensure that the militants in eastern Ukraine allow free access to investigators and do not impede any probe.
