Immediately after the strong earthquake that struck Petrinja on December 29, 2020, seven members of SUZI from Serbia and Croatia participated in the preparation of a preliminary report on the event. The effort was led by the Earthquake Engineering Research Institute (EERI) and the Structural Extreme Events Reconnaissance (StEER) program of the U.S. National Science Foundation. A total of 30 experts from Croatia, the USA, and Switzerland took part in the mission, under the leadership of Prof. Eduardo Miranda from Stanford University, USA. The report is available here