The Russian Kursk region declared a state of emergency, for President Vladimir Putin it is a "big provocation", the confused Washington asked for explanations from Kiev, but until yesterday no one had a precise answer to the question of why a Ukrainian ground unit persistently penetrates Russian territory.

Infantry supported by a dozen tanks and twice as many combat vehicles crossed into Russian territory in the direction of Kursk a few days ago and has already penetrated more than ten kilometers across the border, all the way to the main gas pipeline node in Suja, breaking through two defense lines and a border stronghold.

Defense experts agree that this is an operation by regular Ukrainian forces, not by Russian partisans or pro-Ukraine opposition groups, who have carried out similar, limited-impact incursions several times in the past two years.

The chief of the General Staff of the Russian military forces, Valery Gerasimov, said that nearly 1.000 Ukrainian soldiers are involved in the operation. Russian military bloggers have confirmed that the strike group has reached Suja, where the gas distribution hub is and where the last valves of the gas pipeline leading to Europe via Ukraine are. Civilians were evacuated from both sides of the border – both from Kursk on the Russian side and from the Sumy district on the Ukrainian side.

A great provocation, an even greater enigma

On Wednesday, President Putin assessed the action as a "big provocation" and that "enemy forces are targeting civilian and residential buildings." The Ministry of Defense in Moscow initially announced that "the attack was repelled". And General Gerasimov said that "the attack has stopped" and that Russian forces "continue to destroy the enemies in the border regions", during which they "killed 100 people and wounded another 215".

But this is denied by satellite images and reports from the field. Regional governor Alexey Smirnov declared a state of emergency.

- The operational situation continues to be difficult in the border areas. In order to eliminate the consequences of the entry of enemy forces, I decided to declare a state of emergency - Governor Smirnov said.

Blogger Yuri Kotenok reported about "fierce battles near Suja and Korenevo", and the Ribar portal claims that "the situation continues to deteriorate" and that "Ukrainian forces are advancing towards Suja".

The American think tank Institute for Military Studies (ISW) has confirmed that the Ukrainian strike group has broken through two defense lines and already has prisoners of war.

- Sources on the ground and from other places in Russia indicate that the Ukrainian forces took control of the Suja defense post, as well as the gas distribution station there, after a calculation - reported ISV.

The White House has announced that it is demanding an answer from the Ukrainian authorities to the question of what the goals of the large-scale incursion into Russian territory are.

- Washington supports reasonable actions by Ukraine to stop attacks by Russian forces. We are contacting the Ukrainian military to find out what their goals are - said Karin Jean-Pierre, representative of the White House.

State Department spokesman Matthew Miller dismissed criticism from Moscow.

- To call this a "provocation" is a bit exaggerated, considering that Russia violated the territorial integrity and sovereignty of Ukraine - said Miller, but he did not say what the purpose of the Ukrainian operation was either.

Battle for positions before the US election?

The Russian National Guard announced that the defense of the Kursk nuclear power plant, which is 70 kilometers deeper into Russian territory, has been strengthened. In the neighboring Belgorod region, Governor Vyacheslav Gladkov announced an alert for possible missile attacks.

The only unofficial explanation from Kyiv was given by MP Oleksiy Honcharenko, who confirmed on his social media profile that Ukrainian forces control the valves of the gas pipeline junction in Suja.

- I don't know what the plan is for this penetration, but this should show the Europeans and the Americans that Russia can and should be attacked - noted Honcharenko.

Ukrainian colonel Vladyslav Seleznyov assessed that the attack was "preventive" because 75.000 Russian soldiers approached the border. One possible explanation is that Ukraine is trying to take better positions to prevent an incursion of Russian troops into Sumy, as they did in May in the Kharkiv region.

Other experts say the attack was carried out because of Kiev's concern that they could be without US support if Republican Donald Trump returns to the White House after the November election. Trump claims in the campaign that "when he becomes president, he will quickly end the war in Ukraine."

The penetration is certainly connected with the strategic importance of the energy hub in Suja. This node is key to the Urengoy-Pomari-Uzhgorod gas pipeline, through which 2023 billion cubic meters of gas passed in 14,65, half of the total amount exported from Russia to Europe.