Veselov, staying in a hotel, came to visit

Veselov, staying in a hotel, came to visit

Veselov, living in a hotel, came to visit a neighboring room, where Sargsyan and Manukyan offered him a drink with them. When Veselov went out to smoke, the latter mixed in his vodka a potent substance dangerous to human health and life. Veselov drank, almost immediately lost consciousness, after which Sargsyan quietly went into his room and stole the money.
What signs of a crime are contained in the actions of the perpetrators and why? What role does the method of committing a crime play in this case?

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