Rafael Grossi, the chief international nuclear inspector, has said he saw “the key things I needed to see” and his team was able to gather “a lot of information” during a long-awaited visit to the Russian-occupied Zaporizhzhia plant in Ukraine. The plant’s operator, Energoatom, said on Thursday that Grossi had left the site after a visit that was delayed by several hours because of shelling, but that five International Atomic Energy Agency representatives would remain, probably until Saturday. “We have achieved something very important today and the important thing is the IAEA is staying here – let the world know that the IAEA is staying at Zaporizhzhia,” Grossi said in a video from Russia’s RIA Novosti news agency. He said explanations given to the 14-strong team during the visit, which lasted “a few hours”, were “very clear”. He praised the “dedicated work” of the plant’s staff who were “carrying on professionally with their work” in “very difficult circumstances”. The plant was occupied by Russian forces in March but is still connected to the Ukrainian grid and run by Energoatom employees. The area has come under repeated fire in recent weeks, sparking fears of a radiation disaster. Moscow and Kyiv have traded blame for the shelling, with Ukraine alleging Russia is using the plant as a shield, storing weapons there and launching attacks from the area around it, while Moscow accuses Ukraine of recklessly firing on the zone. Grossi’s comments came after both sides accused each other of trying to sabotage the IAEA visit, aimed at conducting “indispensable nuclear safety and security and safeguard activities”, delaying the mission by several hours. Enerhodar, the city beside the plant, came under fire at dawn, its mayor said, and Russian forces reportedly shelled the pre-agreed route the inspectors were meant to take. Moscow claimed to have thwarted a Ukrainian attempt to capture the plant. Grossi has said the inspection aimed to establish a permanent presence at the plant, but Russian officials had said the inspectors, wearing blue body armour and travelling in white armoured Land Cruisers with UN markings, would remain for just one day. Ukraine said it could not guarantee the team’s security. The energy minister, Herman Halushchenko, told CNN that Ukraine had “fulfilled its international obligations” and done all it could, but the situation around the plant remained “a mess”. Russia’s foreign minister, Sergei Lavrov, said Moscow was “doing everything” for the visiting inspectors “to be able to complete their tasks”. The Russian foreign ministry’s spokesperson, Maria Zakharova, blamed Ukraine for any radiation danger. “The EU is busy with an important decision – whether or not to issue visas to Russians,” she added. “But radiation doesn’t need a visa to cross borders. If something happens at Zaporizhzhia, it will not be about visas, passports or borders.” Robert Mardini, the head of the international committee of the Red Cross, said it was time to “stop playing with fire” and instead protect the plant. “The slightest miscalculation could trigger devastation we will regret for decades,” he said. Mardini said it was encouraging that the IAEA team was inspecting the plant because the stakes were “immense … When hazardous sites become battlegrounds, the consequences for millions of people and the environment can be catastrophic and last many years.” Energoatom said early on Thursday that it had activated emergency procedures and shut down the facility’s No 5 reactor “as a result of another mortar shelling by Russian … forces at the site”. The operator said auxiliary diesel generators had been fired up at the plant’s non-operational reactor No 2 after a power supply line used for the plant’s own needs was damaged by the shelling, but it said unit No 6 “continues to work”. Dmytro Orlov, the mayor of Enerhodar, posted pictures of damaged buildings with smoke spiralling above them on the Telegram messaging app, saying Russian troops had been “shelling since dawn” with mortars, rockets and automatic weapons. Energoatom said the city had come under fire from the air. “A group of Russian K-52 attack helicopters worked over the city, striking residential areas,” it said, adding that one mortar attack struck “in the immediate vicinity” of the plant. President Volodymyr Zelenskiy’s chief of staff, Andriy Yermak, accused Moscow of trying to wreck the inspection, saying Russia was acting like a terrorist state. “It is Russia that is responsible for everything happening at the plant and in Enerhodar,” he said. Moscow, meanwhile accused Kyiv – without evidence – of attempting to sabotage or recapture the Zaporizhzhia plant by sending in “up to 60 people on seven high-speed motor boats”. The IAEA mission was held up at a checkpoint in Novooleksandrivka, about 12 miles from the plant, early on Thursday. Oleksandr Starukh, the administrative head of the Zaporizhzhia region, accused Russian forces of “shelling the pre-agreed route”. Meanwhile, intensive fighting raged across the nearby Kherson region, most of which was seized by Russian forces at the start of the invasion six months ago and where Ukraine began a counteroffensive on Monday.