Clashes between Ukraine and Pro-Russia Militia, Russia Responds

Clashes between Ukrainian security forces and pro-Russian activists are spreading today. There are reports of deaths at three different checkpoints in Slovyansk in the eastern part of the country where most of the fighting has taken place. Russia's military has responded to the violence by announcing "tactical drills" in areas bordering Ukraine. President Obama is threatening to ramp up sanctions on Moscow if it doesn't do more to get pro-Russian troops to lay down their arms. Earlier today reporter Andrew Roth was in Slovyansk for the New York Times.