Ukraine’s SBU security service has arrested five people who allegedly tried to steal nearly $40m (£31m) that was supposed to be used to buy shells for the country’s military in its war against Russia. The SBU said on Saturday it had arrested two senior officials from the ministry of defence. They had allegedly conspired with the chief executive of a little-known arms firm, Lviv Arsenal, over a contract for 100,000 mortar shells. Another employee and an alleged accomplice were also detained. The ministry paid the amount in full in August of last year. The firm failed to deliver any shells and instead diverted some of the cash to a bank account in the Balkans, it was claimed. The SBU said it had charged five people. One was arrested as he tried to flee the country. All face up to 12 years in prison. Meanwhile, Ukraine’s president, Volodymyr Zelenskiy, has tried to clamp down on corruption. He is keen to demonstrate that Ukraine is tackling the problem as it seeks to join the EU and Nato. Both blocs have demanded comprehensive anti-graft reforms. Last September, Zelenskiy removed the defence minister, Oleksii Reznikov, after a series of scandals at the ministry. Although Reznikov was not personally implicated, some of his officials were allegedly caught inflating contracts for food supplied to troops, including eggs. Zelenskiy also sacked the heads of regional military recruitment centres. They had reportedly been taking bribes from men seeking to avoid being sent to the frontline. He replaced Reznikov with Rustem Umerov, a Muslim Crimean Tatar. Umerov has vowed to root out corruption. Since Ukraine’s Maidan revolution in 2014, corruption is less conspicuous in Ukrainian public life that it once was. Civic society has also grown intolerant of graft, at a time when soldiers are dying on the frontline and with no end to the war in sight. Nevertheless, corruption persists. The SBU said it would retrieve some of the stolen state money from Lviv Arsenal’s bank accounts. It said that as a result of “comprehensive measures” its staff had “documented the embezzlement scheme and identified all persons involved”. The arrests came as Russia carried out overnight drone and missile attacks on four regions of Ukraine, wounding at least three people, the Ukrainian armed forces said. According to the air force, eight Shahed-type explosive drones, two Iskander missiles and three S-300 missiles were launched, four of which were shot down. The air force said that civilian sites and “critical infrastructure” were attacked in central Poltava, eastern Donetsk, southeastern Zaporizhzhia and and central Dnipropetrovsk. The prosecutor’s office for Donetsk said one missile had fallen on a residential area in the city, causing injuries. It said a 15-year-old boy and a 35-year-old man had suffered cuts and bruises, while in a neighbouring house a 30-year-old resident had head trauma. Cities and towns close to the sprawling frontline in the east and south have been subject to daily shelling in the near two years since Russia invaded, although Moscow has repeatedly denied targeting residential areas.