Pemex's Deer Park oil refinery near Houston discharged 43,500 pounds of highly toxic hydrogen sulfide gas over more than seven hours in a deadly incident earlier this week, according to the Mexican state-owned company's disclosure to a Texas regulator.

County commissioner Adrian Garcia accused Pemex of failing to use the CAER system or otherwise notify community members about the incident.

The Pemex refinery chemical leak killed 2, injured dozens and forced shelter-in-place orders in Deer Park and Pasadena. They have since been lifted.