  We consider a divergence form hypoelliptic operator consisting of a system of
real smooth vector fields $X_{1},..., X_{q}$ satisfying H\"ormander condition
in some domain $\Omega\subseteq\erren$. Interior $L^{p}$ estimates, $2\leq
p<\infty$, can be obtained for weak solutions of the equation
$X_j^T(a^{ij}X_iu)=X_j^T F^j,$ by assuming that the coefficients $a^{ij}$
belong locally to the space $VMO_X$ with respect to the Carnot--Caratheodory
metric induced by the vector fields.
