BUTTE, Montana — At least 786 children died of abuse or neglect in the U.S. in a six-year span in plain view of child protection authorities — many of them beaten, starved or left alone to drown while agencies had good reason to know they were in danger, The Associated Press has found.

To determine that number, the AP canvassed the 50 states, the District of Columbia and branches of the military — circumventing a system that does a terrible job of accounting for child deaths. Many states struggled to provide numbers. Secrecy often prevailed.

Most of the 786 children whose cases were compiled by the AP were under the age of 4. They lost their lives even as authorities were investigating their families or providing some form of protective services because of previous instances of neglect or violence or other troubles in the home.

Many factors can contribute to the abuse dilemma nationwide: The child protective services system is plagued with worker shortages and a serious overload of cases. Budgets are tight, and nearly 40 percent of the 3 million child abuse and neglect complaints made annually to child protective services hotlines are "screened out" and never investigated.

— The Associated Press