On November 29, an unnamed Crimean security source told Interfax news agency that Russia intends to install a new missile early-warning radar station in Crimea in 2019. The source noted that the station, to be built near the Sevastopol port where Russia’s Black Sea fleet is based, will be able to track ballistic and cruise missiles “from a long distance.” This development comes the same day as Russia’s announcement that it has deployed a fourth S-400 missile battalion in Crimea. On November 25, Russia seized three Ukranian navy vessels off the Crimean Peninsula, escalating tensions.