The Colonial Pipeline company halted shipments of fuel across the eastern United States over the weekend after suffering what executives said was a ransomware attack on Friday. The cyberattack idled a pipeline network that transports nearly half of the East Coast’s fuel supply from Texas to New Jersey. In response, the Biden administration enacted emergency powers, lifting limits on the transport of fuels by road to compensate for any shortages. U.S. officials blamed the criminal gang DarkSide, which mostly operates out of Russia. It was the Colonial Pipeline company’s worst crisis since last summer, when a pipeline rupture in North Carolina spilled at least 1.2 million gallons of gasoline — the largest spill in the state’s history.