"US National Security Advisor Samuel Berger last week gave his Russian counterpart Sergi Ivanov an unclassified written summary based on US Navy intelligence data about the sinking of Russia's Oscar II class (Antey) (Type 949) nuclear-powered submarine Kursk. The data which was collected by two US submarines and a surface vessel that were in the vicinity collecting intelligence on the Russian exercise when the accident occurred, appears to support theories suggesting the accident was caused by a torpedo explosion."