Exclusive: Documents contain months of warnings about possible Ukrainian advance and also reveal concerns about morale

Russia’s military command had anticipated Ukraine’s incursion into its Kursk region and had been making plans to prevent it for several months, according to a cache of documents that the Ukrainian army said it had seized from abandoned Russian positions in the region.

The disclosure makes the disarray among Russian forces after Ukraine’s attack in early August all the more embarrassing. The documents, shared with the Guardian, also reveal Russian concerns about morale in the ranks in Kursk, which intensified after the suicide of a soldier at the front who had reportedly been in a “prolonged state of depression due to his service in the Russian army”.

Ukrainian drone attack causes large explosion at arsenal in Toropets, more than 300 miles north of Ukraine

A Ukrainian drone attack on a large Russian weapons depot caused a blast that was picked up by earthquake monitoring stations, in one of the biggest strikes on Moscow’s military arsenal since the war began.

Pro-Russian military bloggers said Ukraine struck an arsenal for the storage of missiles, ammunition and explosives in Toropets, a historic town more than 300 miles north of Ukraine and about 230 miles west of Moscow.

Russian forces are gathering on Pokrovsk, a logistics base and transport hub, after months of slow, brutal advance

The Russian soldiers sent to storm Ukrainian positions arrived at a graveyard. Around them was the ruined village of Mykhailivka. From above, Ukrainian spy drones watched. One soldier vanished under a tree. Another jogged towards a shell-walloped cottage. Back at a control observation centre, Maj Oleksandr Fanagey muttered a few words.

Seconds later, a Ukrainian kamikaze drone hit a moving Russian. A live video stream showed that he survived but his left leg was injured. The soldier bottom-shuffled towards a patch of grass and tried to pull a bandage from a green backpack. “He will die for sure,” Fanagey predicted. “The enemy doesn’t bother evacuating its wounded.”

Destruction of Ukraine’s energy infrastructure puts botanical garden’s rare and exotic species in danger

Zhanna Yaroslavska showed off a barrel-shaped stove in the middle of a tropical greenhouse. Nearby was a large pile of logs. “It’s a pretty neanderthal arrangement,” she explained. “When the power shuts off we feed the stove with wood. In winter we do this round the clock. Our plants require constant temperatures. They don’t like cold and hot.”

Inside the glass nursery were dozens of rare specimens. All were bromeliads native to the Americas. Silvery wisps of beard-like Tillandsia descended from a pipe. A pineapple poked out of a stem. A screen next to the stove protected a group of starfish-like earth stars, native to Brazil. The collection needed a minimum temperature of 10C, Yaroslavska – a senior researcher – said. Below that everything would die off.

Drone operators and a volunteer medic on the ever-changing dynamics on the frontline of the Ukraine incursion

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Deep into one recent night, at a Ukrainian mobile drone command point hidden amid the fields and forests close to the border with Russia, the largest of six screens flashed with images of the wiggling course of the River Seym, deep inside Russia on the other side of the border. Straddling the river, a thin band was visible, rendered in white by the night vision imaging: a pontoon bridge.

Inside the command point, Anna, Pavlo and Ivan watched the display intently. “Move in closer,” murmured Ivan, the team’s 48-year-old commander. Pavlo pushed a button and the camera zoomed in. “Yesterday, we destroyed this crossing, but they’ve repaired it again, probably in the last few hours,” he said, picking up his phone to send the information to an encrypted group chat of Ukrainian commanders in the area.