(KRON) -- A Foster City resident who was arrested days after a major fire destroyed the multi-story condominium building where he lived will not face criminal charges in the incident, San Mateo County District Attorney Steve Wagstaffe announced Thursday. Keith Tompkins lived at 815 Sea Spray Lane w ith his 93-year-old mother, according to the DA’s office. On the afternoon of Aug. 2, fire investigators said a propane grill located on the balcony of Tompkins’ unit was turned on and left unattended. The grill sparked the blaze, which destroyed some 50 units and displaced nearly 150 condominium residents. Firefighters battle an apartment complex fire at 815 Sea Spray Lane in Foster City, Calif. on Sunday, Aug. 2, 2026. (Photo: KRON4) All residents were safely evacuated, but four firefighters were treated for injuries in the response. On Thursday, the DA’s office stated that “there is no basis for the filing of criminal charges in this case.” Continuing, “The fire investigation written report concluded that the cause of the fire is “undetermined.” The investigator cannot conclude that the fire occurred due to the grill being left on. Even if the cause of the fire was not “undetermined,” the police investigation and interview of Mr. Tompkins established that there was no intent for a fire to occur and that at most there was civil negligence in leaving the grill on.” Aerial view of the apartment fire burning on Aug. 2, 2026, in Foster City, Calif. (Credit: Riley Peterson) “This case does not meet the elements of a criminal offense, and thus criminal charges by this office are not warranted,” the DA’s office wrote. ...read more read less