( CNN ) -- New Jersey Gov . Chris Christie called a fire raging through boardwalk buildings Thursday an `` unthinkable situation '' as firefighters continued to fight the high flames and black smoke in Seaside Park , New Jersey . Christie said 35 engine companies , 15 ladders and 400 firefighters remained on the scene Thursday evening . So far , dozens of businesses have been burned and damaged over four blocks . Some embers hit a condominium , but it was quickly put out , Christie said . Several firefighters have sustained minor injuries , including heat exhaustion and smoke inhalation , Christie said . The fire was still burning along Ocean Terrace Avenue between Stockton Avenue and Lincoln Avenue Thursday evening . Christie said he was notified of the fire shortly after 3:30 p.m . ET . A cause has not been determined . The damage is almost entirely on the boardwalk , Christie said . Fire personnel dug a 20-foot trench on Lincoln Avenue ; `` that 's where firefighters are making their stand right now , '' Christie said . Brisk winds are spreading the fire , Christie said . `` The destruction south of Lincoln Avenue , it 's complete , '' Christie said Thursday . `` I said to my staff , I feel like I want to throw up , and that 's me . After all the effort and time and resources that we 've put in to help the folks in Seaside Park and Seaside Heights rebuild . To see this going on , as I said at the top , is just unthinkable . '' The famous boardwalk of Seaside Heights was thrown into the public eye shortly after Superstorm Sandy tore its famous Jet Star roller coaster into the water . The coaster was removed from the ocean in May , shortly before the boardwalk reopened for business . The FunTown Pier was destroyed by Sandy and partially reopened this summer . Seaside Heights Mayor Bill Akers told CNN in May that rebuilding the boardwalk cost $ 8 million . The total cost for Sandy repairs in Seaside Heights was $ 16 million . Christie explained that fire troops were experiencing water supply challenges because of damage to the system post Sandy , and that teams were drawing lines from Barnegat Bay . CNN affiliate KYW reported that the fire started at Kohr Brothers frozen custard shop on the FunTown Amusement Pier around 2:15 p.m . ET . The fire escalated to six alarms shortly before 4 p.m . ET , according to the same affiliate . Jersey Central Power and Light spokesman Ron Morano said their crews are in the area and that he is not aware of any outages due to the fire . CNN 's Kristina Sgueglia , Julia Talanova , Kevin Conlon , Chris Welch and Rob Frehse contributed to this report .
NEW : Gov . Chris Christie calls huge fire an `` unthinkable situation '' NEW : More than 400 firefighters battling blaze on famous boardwalk , he says . Comment: Part of the boardwalk reopened this summer after the old was destroyed in Superstorm Sandy .