The family of 2-year-old Montrell Williams is demanding answers after the boy’s father was arrested and accused of throwing him into the Bronx River.

The family says the child's 17-year-old mother had reported him missing after a failed visitation on May 11.

Now the family says NYPD and ACS ignored warning signs and are considering legal action. In a news conference, they demanded accountability from both agencies.

“The safety and well-being of New York City’s children is our top priority. We are investigating this case with the NYPD," an ACS spokesperson said in a statement.

The child's 20-year-old father, Arius Williams, is charged with murder and is being held without bail.

"The murder of Montrell Williams is an absolute tragedy, and the NYPD extends our deepest condolences to his family. Our detectives are always committed to conducting complete and thorough investigations, and the arrest of Arius Williams is the first step in the pursuit of justice for Montrell’s death," said an NYPD spokesperson in a statement.