You can choose to call the police, which is the most effective way. The police will arrest him. He is suspected of extortion. As for the evidence, the police will investigate.

The crime of extortion refers to the act of extorting public or private property by threatening or coercing the victim for the purpose of illegal possession. Article 274 of the Criminal Law of People's Republic of China (PRC), whoever extorts or extorts public or private property in a large amount or for many times shall be sentenced to fixed-term imprisonment of not more than three years, criminal detention or public surveillance, and shall also, or shall only, be fined; If the amount is huge or there are other serious circumstances, he shall be sentenced to fixed-term imprisonment of not less than three years but not more than ten years and shall also be fined; If the amount is especially huge or there are other especially serious circumstances, he shall be sentenced to fixed-term imprisonment of not less than 10 years and fined. The crime of extortion is an important crime against property, and its criminal object is public and private property. Some scholars believe that the object of the crime of extortion is complex, including people and public and private property. Starting with the objective elements of the crime of extortion, the object of the crime of extortion can only be property ownership, so its criminal object only includes public and private property, but not people.