Criminal procedure law
Article 80 The public security organ may detain a flagrante delicto or a major suspect in any of the following circumstances:
(1) Being prepared to commit a crime, committing a crime or being discovered immediately after committing a crime;
(2) The victim or a witness on the spot identifies him as a criminal;
(3) criminal evidence is found around him or at his residence;
(four) attempted suicide, escape or escape after committing a crime;
(5) It is possible to destroy or forge evidence or collude with others;
(six) do not speak the real name and address, the identity is unknown;
(7) Being seriously suspected of committing crimes on the run, committing crimes for many times or committing crimes in association.