A police roadblock is set up on the road leading to Wiebo Ludwig's farm near Hythe, Alta. during a search in January. A police roadblock is set up on the road leading to Wiebo Ludwig's farm near Hythe, Alta. during a search in January. (RCMP)The RCMP seized more than 200 items in a raid on Wiebo Ludwig's farm in January, including chemicals that could be used in making bombs, according to documents obtained by CBC News.

Ludwig is the convicted bomber arrested Jan. 8 and held for questioning in connection with a series of pipeline bombings in B.C. At the same time, police raided his Trickle Creek farm and conducted a four-day search. Ludwig was released without being charged.

Among the items carried away were potassium nitrate, a chemical used in fertilizer but also an ingredient in explosives, as well as chemistry books and handwritten notes referring to what police described as "apparent hiding spots for weapons."

Police searched several sheds and buildings on the compound and confiscated guns, ammunition and 75 grams of marijuana, the documents say.

They also took several diaries, including one dated 2000, regarding Karmen Willis, the teen who was shot and killed on the Ludwig farm in 1999 while joyriding with her friends. No one has ever been arrested in that shooting.

Ludwig served time in jail after being convicted of pipeline bombings in the 1990s.

The search in January was part of an investigation into six bombings between October 2008 and July 2009 at natural gas pipelines owned by Alberta-based energy giant EnCana.