(CNN) A Guatemalan father is suing two nonprofits that house migrant children for the US government, alleging his 10-year-old son was forced to take psychotropic drugs and sexually assaulted while in custody.

The father and son, identified in the lawsuit as J.E.B. and F.C.B., allege that US officials forcibly separated them at the border in February 2018. From there, according to the lawsuit, F.C.B. was first placed in the custody of a migrant shelter run by Southwest Key in Arizona, then later transferred to the Shiloh Treatment Center in Manvel, Texas.

The lawsuit alleges that both facilities "acted with fraud, malice and gross neglect" and that staff at both facilities physically assaulted F.C.B. At the Texas facility, the lawsuit alleges the boy "was dosed with powerful psychotropic drugs without parental consent." He was also sexually assaulted by another detained child during the last few weeks of his time in custody at Shiloh, the suit says.

Both the boy and his father were deported last year, according to the lawsuit, which seeks damages for the pain, emotional distress and medical expenses they've allegedly suffered.

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