break loose

Escape from restraint, as in The boat broke loose from its moorings, or He finally broke loose from the school of abstract expressionism. This expression also appears in all hell breaks loose, which indicates a state of fury or chaos, as in When Dad finds out you broke his watch, all hell will break loose, or When the children saw the dead pigeon in the hall, all hell broke loose. [Early 1400s]

The verb has 2 meanings:

Meaning #1: be unleashed; burst forth with violence or noise, as of an emotion or an expression of emotion
  Synonyms: explode, burst forth

Meaning #2: run away from confinement
  Synonyms: escape, get away