Legal analysis: After the public security organ decides to file a case for investigation, it can decide when to arrest the person depending on the circumstances of the case. There is no specific time limit. Generally, the suspect is already in the detention center when the case is filed and investigated. . Under normal circumstances, the public security organs will decide whether to file a case within seven days for the review period of criminal cases that accept reports, accusations, reports, and surrenders. For major and complex clues, the case filing review period can be extended to thirty days with the approval of the person in charge of the county-level public security agency. For particularly major and complex clues, with the approval of the person in charge of the prefectural (city) level public security agency, the case filing review period can be extended to 60 days.

Legal basis: "Criminal Procedure Law of the People's Republic of China" Article 81 For criminal suspects and defendants who have evidence to prove the facts of the crime and may be sentenced to a penalty of imprisonment or more, bail shall be taken If awaiting trial is not enough to prevent the occurrence of the following social dangers, he shall be arrested: (1) Those who may commit new crimes; (2) There is an actual danger of endangering national security, public security or social order; (3) May destroy or falsify evidence, interfere with witness testimony or collude with a confession; (4) May retaliate against victims, informants, or accusers; (5) Attempt to commit suicide or escape. When approving or deciding on an arrest, the nature and circumstances of the crime suspected of being committed by the criminal suspect or defendant, as well as the nature and circumstances of the suspect's or defendant's guilty plea and acceptance of punishment, etc., shall be taken into consideration as to whether there may be a risk to society. Those who have evidence to prove criminal facts and may be sentenced to fixed-term imprisonment of ten years or more, or who have evidence to prove criminal facts and may be sentenced to imprisonment or more, who have committed crimes intentionally or whose identity is unknown shall be arrested. If a criminal suspect or defendant who is released on bail pending trial or under residential surveillance violates the regulations on release on bail pending trial or under residential surveillance, and the circumstances are serious, he may be arrested.