Complex sentence: Milan Zivkovich was well known as heroic and first on the scene journalist, documenting the most catastrophic events in the former Yugoslavia such as the Skopje earthquake, Kakanj mine disaster, floods in Vojvodina, ice mining on the Danube River in Zavoj and many other subjects.
Split into simpler sentences: Milan Zivkovich was well known as heroic first on the scene journalist who documented some of the most catastrophic events in the former Yugoslavia such as the Skopje earthquake, Kakanj mine disaster, floods in Vojvodina. He covered ice mining on the Danube River in Zavoj and many other subjects.