Officials said on Tuesday two pipelines from a 18,000-gallon propane tank in Douglas were ruptured and leaking after a dump truck hit them.
Douglas Police Spokesman Jose Duarte said the truck tried to avoid colliding with a vehicle and struck a wire above a supply store, causing the wires to hit and disconnect two propane lines.
There was no fire or explosion, but dozens of businesses within a half-mile radius of 9th street and Pan American Avenue were closed, according to Douglas Police spokesperson Jose Duarte. He spoke at a news conference that was streamed by KGUN9 News.
Hundreds of people were evacuated from the commercial and industrial district for several hours, according to the Cochise County Sheriff's Department's Facebook page. Some schools let out early due to the incident.
Douglas fire and hazardous-materials units were working Tuesday to cap the pipelines before testing the air quality in the area, which is necessary in order to lift the evacuation.
Two people were treated on scene for non-life-threatening injuries, Duarte said.
Douglas is 100 miles southeast of Tucson, along the U.S.-Mexico border.