Let X be a smooth proper connected algebraic curve defined over an algebraic number field K. Let pi(l)((X) over bar)(l) be the pro-l completion of the geometric fundamental group of (X) over bar = X (K) (K) over bar. Let p be a prime of K, which is coprime to l. Assuming that X has bad reduction at p and the Jacobian variety of X has good reduction at p, we describe the action of the inertia group I-p on the quotient groups of pi(1)((X) over bar)(l) by the higher commutator subgroups. (C) 1995 Academic Press, Inc.