Wolfgang Priklopil kidnapped Natascha Kampusch in 1998 and held her in a windowless cell beneath his house near Vienna until she escaped at the age of 18 in August 2006. Within hours, Priklopil committed suicide.

Prosecutor Thomas Muehlbacher tells the Austria Press Agency that the man, identified only as Ernst H., is being investigated because he made several contradictory statements. H. said in 2006 that he remembered meeting Kampusch at Priklopil's home.

Muehlbacher also told the press agency on Monday that German authorities searched the house of a possible witness over the weekend who claims to have "explosive material" related to the case. More details were not available.

H. has always maintained his innocence.