WASHINGTON, March 27 - New U.S. intelligence assessments say there are more indications than ever that Russia could invade eastern Ukraine, as congressional lawmakers reacted with alarm to Vladimir Putin's rapidly expanding military buildup along the border, Fox News reported.

"The thinking in the U.S. government is that the likelihood of a major Russian incursion into Ukraine has increased," a senior U.S. official told Fox News.

The new thinking is based mostly off analysis of public information, such as heightened rhetoric from Putin and his claims that Russian-speaking people in Ukraine face "brutality." He is building a public case for more military action, according to senior U.S. officials.