Alexei Navalny is a Russian government official. He is a big critic of the Russian president, Vladimir Putin.
On August 20, Navalny flies from Tomsk, Serbia, to Moscow, Russia. He drinks hot tea at the airport. He does not eat anything. However, he starts to feel very sick on the plane. The pilots must land in Omsk, Russia. Navalny falls into a coma. He ends up in a hospital in Berlin, Germany.
Doctors do some tests. The find poison in his body. They find Novichok. Novichok is a Russian chemical. It is very dangerous to people.
German officials ask Russia to explain the situation. Some people think that the Russian president wants to kill Navalny. Russia uses Novichok in the past, too. However, the Russian president says that it is not true.
Difficult words: critic (a person who says bad things about somebody else), coma (a serious situation when someone looks like he is sleeping, and he does not wake up), poison (a dangerous thing that can kill a person or hurt some parts in the body), chemical (a thing that you can find in nature and that scientists can make).