How did the police catch people and know where they were?

1. You can ask the suspect's family, because the "arrest" of the suspect legally means being summoned by the public security organ (criminal summons or public security summons), and the public security organ will notify the suspect's family. According to relevant laws and regulations, after a criminal suspect is summoned by a public security organ, the public security organ shall promptly notify the family members of the summoned person by telephone, text message, fax, etc.

2. If the suspect's family has not received the notice, they can bring their ID cards, household registration books and other materials to prove their kinship with the suspect, and go to the police station to ask whether the suspect (his relatives) have been arrested, the place and duration of detention.

legal ground

After being summoned by the public security organ in the first paragraph of Article 83 of the Law of People's Republic of China (PRC) on Public Security Administration Punishment, the violator shall be inquired and verified in time, and the time for inquiry and verification shall not exceed eight hours; If the situation is complicated and the punishment of administrative detention can be applied according to the provisions of this law, the time for questioning and verification shall not exceed 24 hours.