Welf. & Inst. Code, § 340

(a) Whenever a petition has been filed in the juvenile court alleging that a minor comes within Section 300 and praying for a hearing on that petition, or whenever any subsequent petition has been filed praying for a hearing in the matter of the minor and it appears to the court that the circumstances of his or her home environment may endanger the health, person, or welfare of the minor, or whenever a dependent minor has run away from his or her court-ordered placement, a protective custody warrant may be issued immediately for the minor.

(b) A protective custody warrant may be issued without filing a petition under Section 300 if the court finds probable cause to support all of the following:

(1) The child is a person described in Section 300.

(2) There is a substantial danger to the safety or to the physical or emotional health of the child.

(3) There are no reasonable means to protect the child’s safety or physical health without removal.

(c) Any child taken into protective custody pursuant to this section shall immediately be delivered to the social worker who shall investigate, pursuant to Section 309, the facts and circumstances of the child and the facts surrounding the child being taken into custody and attempt to maintain the child with the child’s family through the provision of services.

(d) (1) Nothing in this section is intended to limit any other circumstance that permits a magistrate to issue a warrant for a person.

(2) Nothing in this section is intended to limit a social worker from taking into and maintaining temporary custody of a minor pursuant to paragraph (2) of subdivision (a) of Section 306.