Police are investigating more than 100 cases of online trade in homemade explosive materials, brought to light after Norway’s shooting spree perpetrator used homemade explosives in his recent terrorist attacks, officials said Wednesday.

“Local police are investigating individuals who have either sold poisonous or explosive materials online or have postings related to the two on their cafes or blogs,” said a police official.

Investigators from the Cyber Terror Response Center, the National Police Agency’s cyber crime unit, have found 6,932 sites that inform members on the manufacture of bombs or methods of suicide.

Among the sites found during a recent investigation in June, police found 139 cases in which poisons or homemade explosives and related materials were traded online, and are currently considering further investigations.

Police believe that since these posts have gone beyond simple showcasing of products and have actively traded items with money, they can apply charges under the gun, sword and explosive control act.

One of the blogs found on a famous Internet search portal showed the detailed process of making a homemade bomb using shoestrings as a fuse.

Another online café, which has some 250 members, showed how to make knifes, daggers, homemade explosives, smoke bombs and other contraband items.

The site also gave directions on how to obtain the necessary chemicals and items.

A quick online search showed many different websites offering detailed instructions on making explosives to be used anywhere from simple pranks to causing physical harm.

“We cannot only prosecute those who trade explosive materials and firearms but also those who inform others on the construction and use, as it can be seen as an act of sedition,” said the official.

“Depending on the gravity of the offenses we might simply ask the portal operators to delete the posts, or aggressively investigate the case and seek prosecution,” he added.

By Robert Lee (robert@heraldcorp.com)