Authorities said Friday they have arrested 40 suspects and seized thousands of videos, CDs and DVDs as part of a yearlong crackdown on child pornography.

Officials detailing what they said involved months of undercover investigation said police also confiscated dozens of PCs, laptops and hard drives in an international operation carried out in cooperation with authorities in neighboring Germany.

Police in Italy made two arrests in connection with the investigation, which was code-named Operation Max, Austrian authorities said.

Mario Hubmann, a senior police inspector with Austria's Federal Criminal Investigations Bureau, said the suspects range in age from 16 to retirees in their 60s, including two government employees and a radiologist.

Hubmann said the lurid images seized in raids on scores of homes nationwide included photos of one of the suspects with the man's 17-year-old stepdaughter.

He said German authorities were examining a video showing a 4-year-old child being sexually abused.

Austrian officials said the latest case was linked to the discovery in February of a child porn ring involving nearly 2,400 suspects from 77 countries.

That investigation began last July, when a man working for a Vienna-based Internet file-hosting service approached authorities at Austria's interior ministry to say he had noticed child pornography being downloaded during a routine check.

Within a 24-hour period, investigators recorded more than 8,000 hits from 2,361 computer I.P. addresses in 77 countries ranging from Algeria to South Africa, officials said. They said users paid to download video of children under age 14 being sexually abused.

Hubmann said the server was located inSt. Petersburg, Russia, and since has been shut down.

The FBI was investigating about 600 suspects in the United States, German authorities were following leads on another 400 people and France was looking into more than 100 others, the ministry said.