Madrid - Spanish police have detained 121 people in their biggest swoop so far against child pornography on the internet, police said Wednesday.

Two of the detainees made their own material, using children belonging to their family circles, the sources said.

Police identified 250 addresses in dozens of provinces where pornographic material was downloaded and distributed.

More than 800 police participated in the operation, seizing millions of files, including some material described as hard-core.

The investigation was launched in July 2007. The suspects included people of different ages and professions. (dpa)