They were searching for any antique left by the former owners of what had been a restaurant and home. The team descended into the basement and did find a few artifacts. Then came something that was not expected. The group spotted a dark crawl space seemingly hidden by boards on the basement's eastern wall. Was this an entrance to the supposed tunnel system that had been rumored about for years?
Tunnels in Chinatown were rumored to have been so vast that patrons could travel from one end of the neighborhood to the other and never see daylight. One tunnel was rumored to have extended under the dividing railway tracks so that men from the White side of town could reach Chinatown speakeasies undetected.
Since the discovery of the tunnel entrance, the City of Fresno has been using ground penetrating radar to map out the extent of the underground network. Some local groups have started to lead tours, guiding visitors to the basement of a barbershop where mysterious doorways are sealed with concrete.
A more extensive article from the LA Times can be found here.