The trial in France of 66 people accused of sexually abusing children in exchange for giving their parents cigarettes and money has opened in the western city of Angers.

Proceedings began Thursday in what observers have called one of France's biggest criminal trials. Court officials began reading out the prosecution case, which is more than 400 pages long.

The hearings, expected to last four months, are taking place in a specially built courtroom.

Prosecutors say the defendants formed a ring that abused at least 45 children, ranging in age from just a few months to early teens.

The abuse allegedly took place between 1999 and 2002.  Prosecutors say some parents abused their children or bartered them for cigarettes, food or small sums of money.  Several of the defendants face 30 years or more in prison if convicted.

Some information for this story provided by AP and AFP.