  Dilaton-axion gravity with $p U(1)$ vector fields is studied on space-times
admitting a timelike Killing vector field. Three-dimensional sigma-model is
derived in terms of K\"ahler geometry, and holomorphic representation of the
SO(2,2+p) global symmetry is constructed. A general static black hole solution
depending on $2p+5$ parameters is obtained via SO(2,2+p) covariantization of
the Schwarzschild solution. The metric in the curvature coordinates looks as
the variable mass Reissner-Nordstr\"om one and generically possesses two
horizons. The inner horizon is pushed to the singularity if electric and
magnetic SO(p) charge vectors are parallel. For non-parallel charges the inner
horizon has a finite area except for an extremal limit when this property is
preserved only for orthogonal charges. Extremal dyon configurations with
orthogonal charges have finite horizon radii continuously varying from zero to
the ADM mass. New general solution is endowed with a NUT parameter, asymptotic
values of dilaton and axion, and a gauge parameter which can be used to ascribe
any given value to one of scalar charges.
