BERKELEY TOWNSHIP, N.J.—A young lifeguard was killed and seven other people, including three other lifeguards, were injured when lightning struck a Jersey Shore beach Monday afternoon, authorities said. New Jersey Gov. Phil Murphy confirmed that a lifeguard in Berkeley Township was killed in the afternoon. It marked the second death of a young lifeguard at the Jersey Shore in a little over a week. Ocean County Sheriff Michael Mastronardy said the others were taken to hospitals with injuries that were not considered life-threatening. “Our hearts are with the family and friends of the young lifeguard killed by today’s horrific lightning strike on the beach in Berkeley Township, and we pray for a full recovery for those injured,” Murphy, the state’s Democratic governor, wrote on Twitter. “I’ve spoken to Mayor Carmen Amato and offered the full support and assistance of our administration during this difficult time.” Amato said his township’s beaches …