PASADENA, TX (KTRK) -- One person was killed and three people were injured after a chemical tank explosion at PeroxyChem plant in Pasadena.Around 12:30pm Saturday, an explosion went off at the plant. Officials with PeroxyChem, located on Bay Area Blvd., tell Eyewitness News that one contractor and two employees were taken to the hospital.According to officials, plant employees and contractors were conducting a routine function when the contractor's equipment exploded. Police say a rupture caused a spill, exposing at least two people to chemicals. A third person sustained a broken arm."We are deeply saddened to report the loss of the contractor. Our thoughts and prayers are with his family and loved ones," plant officials said in a release.The incident is under investigation.