The Transportation Security Administration (TSA) on Tuesday issued a second security directive meant to strengthen critical pipelines against cyberattacks in the wake of the crippling ransomware attack on Colonial Pipeline earlier this year.

Under the directive, owners and operators of critical pipelines transporting gasoline or other hazardous liquids are required to take specific security measures to protect against ransomware attacks, develop recovery plans in the event of an attack and review their existing cybersecurity plans.

The first security directive was issued by TSA, which falls under the Department of Homeland Security (DHS), in May, and required pipeline companies to report cybersecurity incidents within 12 hours to the Cybersecurity and Infrastructure Security Agency (CISA).