MOSCOW (Reuters) -Russia accused Ukraine on Saturday of using "terrorist activities" to try to disrupt its presidential election and former President Dmitry Medvedev decried as "traitors" the scattered protesters who have tried to set fire to voting booths and pour dye into ballot boxes.
The Ukraine war has cast a shadow over voting in the election, which is all but certain to hand President Vladimir Putin six more years in the Kremlin but has been marked by sporadic acts of protest.
On the second of three days of voting, the Russian foreign ministry said Kyiv had "intensified its terrorist activities" in connection with the election "to demonstrate its activity to its Western handlers and to beg for even more financial assistance and lethal weapons".
It said that in one such incident, a Ukrainian drone had dropped a shell on a voting station in a Russian-controlled part of Ukraine's Zaporizhzhia region.
The state-run TASS news agency quoted a local election official as reporting no damage nor injuries when the explosive device landed five or six metres (yards) from a building housing a polling station before it had opened in a village about 20 km (12 miles) east of the city of Enerhodar.
Reuters could not independently verify the incident.
There was no immediate comment from officials in Ukraine, which regards the election taking place in parts of its territory controlled by Russia as illegal and void.
Meanwhile the head of the electoral commission, Ella Pamfilova, said that in the first two days of voting there had been 20 incidents of people trying to destroy voting sheets by pouring various liquids into ballot boxes, as well as eight cases of attempted arson and a smoke bomb.
Commenting on the incidents, Medvedev said those responsible could face treason sentences of 20 years.
"This is direct assistance to those degenerates who are shelling our cities today," he posted on social media, referring to Ukrainian attacks.
On Sunday's final day of voting, supporters of late opposition leader Alexei Navalny have called on people to turn out en masse at noon in a rolling protest against Putin in each of the country's 11 time zones.
UKRAINIAN ATTACKS
Russian media quoted Kremlin spokesman Dmitry Peskov as saying Putin had been receiving military reports in recent days of attempted attacks by saboteurs in the border regions of Belgorod and Kursk, including several incursion attempts overnight, all of which he was quoted as saying were thwarted.
A senior Ukrainian intelligence official said on Thursday that armed groups he described as Russians opposed to the Kremlin had turned the regions into "active combat zones".
On Saturday, Kyrylo Budanov, head of Ukraine's military intelligence directorate, said the groups, the Freedom of Russia Legion, the Siberian Battalion and the Russian Volunteer Corps, were "becoming a force" with unified principles.
The groups were fighting "quite well" and were not going to stop any time soon, he said in a Ukrainian television interview, adding, "We will try to help them to the best of our ability."
In the Belgorod region where cross-border attacks from Ukraine have become part of daily life, Governor Vyacheslav Gladkov reported the deaths of a man and a woman in a missile attack, and later in the day, one injury, after he said Russian defences shot down 15 rockets approaching the regional capital.
Video obtained by Reuters showed fires ablaze and air raid sirens sounding on the empty streets of Belgorod city.
Dmitry Azarov, governor of the Samara region 850 km (530 miles) southeast of Moscow, said the Syzran refinery was on fire following a drone attack but an attack on a second refinery had been thwarted.
The fire was later brought under control, officials said, but the incidents highlighted Ukraine's ability to strike hundreds of miles (km) inside Russia to target its energy industry. Two other big refineries were set on fire this week.
In his nightly video address, Ukrainian President Volodymyr Zelenskiy said it had become clear in recent weeks that Ukraine could use its weapons to exploit what he called vulnerabilities in the "Russian war machine."
Russia mounted its deadliest attack in weeks on Friday when its missiles hit a residential area in Ukraine's Black Sea port city of Odesa, killing at least 21 people and wounding more than 70.
PUTIN'S DOMINANCE
Putin's hold on power is not under threat in the election. Aged 71 and in office as president or prime minister since the last day of 1999, he dominates Russia's political landscape.
None of the other three candidates on the ballot paper - veteran Communist Nikolai Kharitonov, nationalist Leonid Slutsky or Vladislav Davankov, deputy chairman of the lower house of parliament - has mounted any credible challenge.
Overall turnout - an important indicator for Putin as he attempts to demonstrate the whole country is behind him - rose above 58% on the second day of voting.
The rate in Belgorod region was over 76%. Turnout was also high in Russian-controlled regions of Ukraine.
Russia's governing party, United Russia, said it was facing a widespread denial of service attack - a form of cyberattack aimed at paralysing web traffic - and had suspended non-essential services to repel it.
State news agency RIA quoted a senior telecoms official as blaming the cyberattacks on Ukraine and Western countries.