Summertime and the warring in eastern Europe is wearing on Ukraine, as Moscow makes good on threats to intensify its assaults on the battle-scarred country. On Monday morning, Reuters reported that the Russian defense minister, Sergei Shoigu, instructed Russian forces to prioritize destroying Ukraine’s long-range missile and artillery weapons, according to a ministry statement. That news followed a strike on Sunday in which a volley of ten missiles hit the southern Ukrainian city of Mykolaiv. 

The website Ukrinform reported that the missiles were “presumably launched by an S-300 system,” which a Ukrainian official characterized as “a powerful weapon of destruction inflicting maximum damage.” It was not immediately clear what targets the Russians were singling out, but Mykolaiv’s mayor, Oleksandr Senkevych, said that an industrial and infrastructure site had been hit. Whether there were any casualties was not immediately clear. Any attack on Mykolaiv, a strategic shipbuilding center, would be consistent with a major Kremlin goal: to cut off Ukraine’s Black Sea access. 

In the early hours of Monday, Russian forces shelled Nikipol, a city on the Dnieper River east of Mykolaiv and due north of the Crimean peninsula. The governor of the Dnipropetrovsk region, Valentyn Reznichenko, posted on Telegram that Russian troops hit Nikopol several times with anti-aircraft guns. He said more than 60 shells were directed at residential quarters and city infrastructure.

Russian attacks against cities that flank Ukraine’s Black Sea littoral are also consistent with a fresh threat from the Kremlin leveled at Ukraine should the latter try to retake Crimea, which Russia seized in 2014. The Times of London reported that at a meeting with World War II veterans at Volgograd, the deputy head of Russia’s security council, Dmitry Medvedev, a former president of Russia, said that Ukraine was “trying to snap back, and some exalted bloody clowns who pop up there periodically with some statements, are trying to threaten us — I mean an attack on Crimea, and so on.” Mr. Medvedev followed that by saying “the consequences are obvious that if something like this happens, there would be a ‘doomsday’ for all of them there, very fast and hard.”

Probably very little of the “snapping back” that is such a thorn in the sides of  Mr. Medvedev and President Putin has to do with Crimea right now. It is mainly the Ukrainian resolve in general, in the form of counter offensives — and particularly one that may be imminent at the pivotal Black Sea port of Kherson, which at the moment at least is still Russian-occupied. The Telegraph reported that in recent days Ukraine’s deputy prime minister, Iryna Vereshchuk, urged the half of the city’s original population of 300,000 that had not yet fled since the Russian takeover in March to do so now, ahead of what she warned “will be a huge battle.” 

Complicating any exodus from Kherson, the Telegraph noted, is that the only way out “is a road leading northwest to the city of Zaporizhzhia, which sometimes comes under fire,” and that “en route, there are also around 50 Russian checkpoints — many apparently set up mainly to extract bribes and harass refugees.” As the Sun reported last week, though, President Zelensky has given the order to retake the strategically vital southern flank, which would include Kherson. How much lift the arrival of advanced weapons like the HIMARS mobile artillery rocket system supplied by Washington will give to Kyiv remains to be seen as the southern showdown looms.

As if Mr. Zelensky did not have enough on his plate, the Ukrainian leader appears to have a domestic house badly in need of better oversight. The Guardian reported that Mr. Zelensky has fired the head of Ukraine’s domestic security agency, the SBU, as well as the state prosecutor general, citing dozens of cases of collaboration with Russia by officials in their agencies. According to the paper, “the abrupt sackings of SBU chief Ivan Bakanov, a childhood friend of Zelensky, and the prosecutor general, Iryna Venediktova, who played a key role in the prosecution of Russian war crimes,” were announced in executive orders posted on the president’s website on Sunday.

The incidents of treason and collaboration are almost too numerous to count, but indeed they are being counted: Mr. Zelensky said that 651 cases of alleged treason and collaboration had been opened against prosecutorial and law enforcement officials. That led the Guardian to conclude that “the sheer number of treason cases lays bare the huge challenge of Russian infiltration faced by Ukraine as it battles Moscow in what it says is a fight for survival.”