A natural gas pipeline ruptured Monday morning near Plymouth, Washington.
Officials confirm that four people were injured in the resulting explosion, and the concussion could be felt three to six miles away.
The cause of the blast is still uncertain according to fire officials.
The first explosion sent shrapnel flying, puncturing a large tank storing the liquefied natural gas, causing a leak and the risk of a much larger explosion.
Benton County deputies went door to door, evacuating homes and businesses within a two-mile radius -- almost 1000 residents -- to the fairgrounds on the other side of the Columbia River.
According to Williams Northwest Pipeline spokesperson Michele Swaner, all employees are accounted for and though one was burned, he is expected to recover.
The Tri-Cities Herald described “a large cloud of fumes floating in the area as the gas escaped into the air,” and reported rescue workers feeling ill as a result of the fumes. Natural gas has come under fire lately as critics claim fracking methods used to access underground deposits are harmful to the environment, contaminating water supplies and damaging ecosystems, with concerns that blasts possibly contribute to increased seismic activity. Damaged, leaking pipelines can also pollute surrounding areas and contribute to greenhouse gas emissions.
Williams Northwest shut down the LNG pipeline, allowing the gas to dissipate to reduce the risk of further ignition while workers repair the pipeline and the storage tank.