 Complete the following phrase:  Since his sporting career began in 1982, Berg-Knutsen is considered one of Norways most prominent sport shooters, having achieved numerous successes in rifle shooting events at the ISSF World Championships, ISSF World Cup, and European Championships. He had also won a total of three medals at the ISSF World Championships, including two golds 1998 in Zaragoza, Spain, and 2006 in Zagreb, Croatia. One of the highlights of his career occurred at the 