Complex sentence: One of their contacts is Lyle Dylandy, the second Lockon Stratos, who provided them with information on Celestial Being's attack on a prison, in which Kataron members free the prisoners.
Split into simpler sentences: One of their contacts seem to be Lyle Dylandy, the second Lockon Stratos. He provided them with information on Celestial Being's attack on a prison, in which Kataron members free the prisoners.