Bound states of little strings and symmetric orbifold conformal field theories

We study BPS bound states of little strings in a limit where they realize monopole strings in five dimensional gauge theories. The latter have gauge group U(M)(N) and arise from compactification of (1,0) little string theories of type A(M-1) x A(N-1). We find evidence that the partition function of a certain subclass of monopole strings of charge (k,..., k) (k >= 1) is expressible as the partition function of a symmetric orbifold sigma model, whose target space is precisely the symmetric product of the moduli space of monopoles with charge (1,..., 1).