Blew the whistle

• Was a rat
• Squealed
• Was a snitch
• Spilled the beans
• Told secrets
• Told all
• Sqealed, so to speak

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Tattle \Tat"tle\, v. i. [imp. & p. p. Tattled ; p. pr. & vb. n. Tattling .] [Akin to OE. tateren, LG. tateln, D. tateren to stammer, and perhaps to E. titter.] To prate; to talk idly; to use many words with little meaning; to chat. The tattling quality ...

Wiktionary Word definitions in Wiktionary
vb. (en-past of: tattle)