DONETSK, Ukraine -- Intense fighting broke out between pro-Russian separatists and Ukrainian security forces in the country's eastern region, killing at least 13 soldiers and further raising tensions just three days before a pivotal national election.
The clashes prompted Ukrainian officials to call for an emergency meeting of the U.N. Security Council and broke several days of relative calm amid reports of divisions in the separatist ranks. The United States and its European allies have accused Russia of sowing chaos in eastern Ukraine to throw off the election, and they have threatened Moscow with additional sanctions if the vote is disrupted.
Acting President Oleksandr Turchynov said Thursday that the Ukrainian troops were killed when rebels attacked a checkpoint with automatic weapons and rocket-propelled grenades near the town of Volnovakha, about 12 miles south of this city. A regional health official later said 16 people had died.
Witnesses told the Associated Press that the attackers arrived in a bank's armored car, which the unsuspecting soldiers waved through the checkpoint, only to be mowed down at point-blank range.
The Foreign Ministry also said Ukrainian border guards repelled an attack Wednesday by "several groups of armed militants" who were trying to enter the country from Russia. Describing one of the attacks, the Interior Ministry said in a statement that three trucks and a sport-utility vehicle attempted to cross the border in the Luhansk region late Wednesday, but it said the border guards fired warning shots, and the cars raced back into Russia.
Ukrainians are scheduled to go to the polls Sunday in presidential and mayoral elections that could determine the makeup of the country and its alignment between Russia and the West. Pro-Russian separatists in its eastern region have declared the vote illegal and been actively seeking to halt it.
At district election commission No. 42 in Donetsk, for example, a group of about 10 armed men from the self-proclaimed Donetsk People's Republic arrived to tell the employees their work was done. Their message was clear: There will be no presidential election in Ukraine this Sunday if the pro-Russian separatists have their way. "I was terrified and locked the door," said receptionist Elvira Maslova, 51, who works down the hall.
Separatists have targeted other election offices in the Donetsk region, which is home to about 3.5 million voters, or nearly 10 percent of the nation's voters, a regional election official said.
On Thursday, armed militants closed another of the Donetsk region's district election commission offices, each of which organizes and oversees voting for several polling stations.
At other locations, some local officials were abducted, but usually released a short time later, and at least one was beaten, said former Ministry of Justice employee Valeriy Zhaldak, who is serving as elections adviser to Donetsk's regional government. In the city of Horlivka, the person heading the district election commission apparently crossed to the separatist side and was proclaimed the "people's mayor," Mr. Zhakdak said. "There are always fights somewhere," he said.
Mr. Zhaldak, who is working out of a hotel because pro-Russian separatists still occupy the main regional administration building, said some election offices have been relocated from hotspots, such as rebel-held Slovyansk. Some local elections officials also have agreed to hide voter records, ballot boxes and other materials in their homes.
Denis Pushilin, a leader of the People's Republic of Donetsk, who sees the national government as an occupier, said the elections are illegal in their territory, but he denied using violence to halt them. "We think it's inappropriate to hold presidential elections in a neighboring country," he said in an interview. "As for disrupting the elections, I wouldn't use this term. I'd say we are opposing them through civilized methods, with the help of law enforcement and police. We are not advocates of violence."