Slovyansk, Ukraine -- A shootout at a checkpoint run by pro-Russian militants near the town of Slovyansk that killed at least three people Sunday highlighted that a truce reached days earlier by diplomats in Geneva was fraying in eastern Ukraine. At around 2 a.m., four cars drove toward the checkpoint and their occupants opened fire, killing three local men who were standing guard, according to pro-Russian militants who control the town. Life News, a Russian tabloid television channel, reported that the defenders of Slovyansk had found a business card of the leader of the Ukrainian nationalist group Right Sector, Dmytro Yarosh, in the belongings said to have been left behind by one of the attackers, along with stacks of dollars and guns.