Lucius knew that it wasn’t true. He had researched it and found out that the only creature responsible for the attacks in 1942/43 was a basilisk. The basilisk was capable of killing people, if you looked directly into its eyes. Petrifying was only possible, when you look indirectly into the eyes of a basilisk like into a mirror or another mirroring object. He would bring this issue to attention, in order to fix this mistake.