Authorities say investigators didn't have enough evidence until last month to take custody of a 7-year-old Wyoming boy who was allegedly kept in an outdoor cage, despite requests last year to check on his welfare.

The Laramie Daily Boomerang reported Thursday ( Albany County Sheriff Dave O'Malley expressed frustration that deputies couldn't act sooner, but initial investigations didn't provide enough evidence.

Authorities took the boy into protective custody July 24 and arrested his mother and her boyfriend on child-abuse charges.

Authorities say the child was kept in the 6-by-6-foot cage off and on for three weeks. O'Malley says he's been told the boy is doing well now.

The Associated Press typically does not identify abuse victims and is withholding the suspects' names to avoid identifying the child.