Barrow, Alaska ? Ridges of sea ice packing car-sized chunks of the cold stuff slammed onto a road in Barrow, Alaska, in quantities not seen in nearly three decades.

Two ice surges, known to Alaska Natives as ivus, stunned residents who had never seen such large blocks of ice rammed ashore.

Ivus are like frozen tsunamis and crash ashore violently. They have killed hunters and are among the Arctic’s most feared natural phenomena.

The ivus crashed ashore Tuesday after strong winds from Russia and eastward currents began pushing pack ice toward Barrow last weekend, said North Slope Borough disaster coordinator Rob Elkins.