  In this paper we study the classical dynamics of long strings in AdS3,
generalizing our previous study, arXiv:1410.3424 [hep-th], to rotating strings
and BTZ black holes. As in the non-rotating case, BTZ black holes are generated
in the large tension limit, in which string back-reaction must be taken into
account. When back-reaction is properly accounted for, collapsing heavy,
physical, rotating strings do not generate naked singularities but only BTZ
black holes, including extremal ones. The rotating string must contain
world-sheet excitations in order to have consistent equations of motion; we
describe such additional degrees of freedom implicitly in terms of an effective
equation of state.
