The 5,500-mile Colonial Pipeline began restarting its operations Wednesday evening after a ransomware attack that crippled the system for six days and led to gas shortages across the Southeast, according to CNN. Pipeline operators have cautioned that it could take time for service to return to pre-attack levels.

Following the attack, for which authorities believe criminal group DarkSide is responsible, gasoline demand in Georgia, Florida, South Carolina, North Carolina and Virginia spiked by a collective 40.1%. Brian Zimmerman, owner of Zen Windows, Charlotte, N.C., documented the effects of the crisis on Wednesday prior to the system’s restart.

“We started seeing long lines and panic buying yesterday,” Zimmerman said. “This caused widespread shortages with most stations being out of gas. They are saying we might not see more until Friday or the weekend. We’ve had one crew run out of gas already and we’ve had to delay their installs until they find some. We’ve delayed several installs and measures that are larger distances away for the time being. We just have to be smart about when/where we are going. We are hoping that this will be resolved by next week. Fortunately, most customers completely understand because they are dealing with the same issues.”

Maurice Duvic, owner and president of Chattahoochee Windows and Doors in Smyrna, Ga., experienced similar struggles.

“A lot of gas stations were out of gas [on Tuesday],” Duvic said. “We are cutting back on all sales appointments. Installers are going to jobs if they have enough gas. Hope this is short term. Panic is the cause for most of the shortage. Prices rose 20-30 cents [on Tuesday].”