India, July 13 -- South Carolina Senator Lindsey Graham visited a secret Ukrainian military drone factory just one day before his sudden death Saturday evening at age 71.

The visit came during his trip to Ukraine, hours before his office announced his passing from a "brief and sudden illness."

Graham toured a production facility belonging to Ukrainian defense company SkyFall, according to Ukraine Pravda, as cited by the New York Post. During the visit, he also met Ukrainian President Volodymyr Zelensky, along with his House colleague Rep Michael McCaul (R-TX).

The plant produces Ukraine's "Vampire" bomber drones, also called "Baba Yaga," which are capable of carrying explosive charges behind enemy lines. Graham said the US could learn ...