(KRON) -- A massive house fire caused by an underground gas explosion erupted on East Lewelling Boulevard in Hayward on Thursday morning. Six people were transported to the hospital as a result of the blaze, according to Alameda County Fire Department Ofificals. Three structures on two separate lot s were damaged in the explosion and subsequent fire, officials said. No fatalities have yet been reported. The condition of those hospitalized was not immediately known. KRON4 News has confirmed one patient is in stable condition. The explosion leveled at least one house, causing significant damage to at least two others, according to Deputy Fire Chief Ryan Nishimoto. Earlier, officials said it was possible two people remained unaccounted for. However, as of around 3:30 p.m., all residents in the area had been accounted for, according to the Alameda County Fire Department. Viral video of man hiding in trunk of Waymo raises safety concerns Pacific Gas and Electric confirmed that the fire was caused by an explosion that occurred around 9:35 a.m. According to PGE, the utility was notified around 7:35 a.m. that a third-party, non-PGE crew damaged an underground gas line while digging on Lewelling. PGE dispatched crews to the scene that worked to isolate the damaged line and stop the flow of gas. Due to damage to gas facilities by the contractor, gas was released at multiple locations. The flow of gas was stopped about 10 minutes prior to the explosion. Eight engines and two trucks responded to the incident, according to Alameda County Fire. PGE crews are working with first responders to make the area safe. Hayward Mayor Mark Salinas issued a statement about the incident, saying: "Earlier today, there was an explosion in the unincorporated area of Hayward. While the incident is not directly under my jurisdiction, my office has been in constant contact with PGE, Hayward Fire Chief Hamre, and Assembly Member Liz Ortega’s office. We are providing support where needed. Like many of you watching the scenes unfold on television, I am watching closely and praying that no one is seriously hurt. We will continue to monitor the situation and share updates as we receive them." Video from the Citizen App showed a massive plume of smoke emanating from the location at 868 East Lewelling, not far from Interstate 238. There was a power outage in the area, according to PGE's outage map. Photo: Citizen The southbound offramp off I-238 at East 14th Street was closed due to fire department activity, according to the California Highway Patrol. Southbound 238 to East 14th was shut down along with Mission Boulevard to Paradise Boulevard. Drone video from the scene showed a massive amount of smoke and apparent devastation from the fire. The National Transportation Safety Bord said it was sending a team to Hayward to investigate the explosion. Bay City News contributed to this story. ...read more read less