Durham firefighters responded to and cleared a call reporting the smell of gas near a coffee shop that exploded last week about twenty minutes before a contractor told 911 he had struck a gas line, according to the city.

The city of Durham had previously released the second 911 call—placed at 9:37 a.m.—from an unnamed contractor saying a gas service line had been hit and requesting police presence. Firefighters responded to that call within minutes, emergency officials have said, and immediately began evacuating the Kaffeinate coffee shop. The explosion occurred during the evacuation, killing Kaffeinate owner Kong Lee and injuring twenty-five others, including nine firefighters.

New information from the city shows there was an earlier 911 call, made at 9:11 a.m.

“I’m downtown near [Durham School of the Arts] and there’s a very strong gas smell,” the unidentified caller says. “I was driving through there but as I was approaching the intersection right before you get to where the school begins—that block—it’s just a really strong smell of gas.”

According to the city, a fire engine was dispatched to that call at 9:13 a.m. and arrived at the corner of North Duke and Morgan streets at 9:17 a.m.

“The firefighters could not detect a smell of gas at the intersection, continued on to the entrance of the school parking lot and attempted to make contact with the 911 caller to get more information about where she smelled the odor,” the city said in a statement. “Those efforts were unsuccessful.”

Firefighters then “began a slow canvas,” driving around the area, including the DSA, and pausing “for almost a minute” on Morgan Street between North Duke and Gregson Streets “but detected no odor of gas.” The building that would explode less than an hour later—around 10:07 a.m.—was at 115 North Duke Street, about a half-block south.

According to the city, firefighters noticed a gas service nearby and “believed a pressure related venting of gas occurred” and cleared the scene. The same unit was later dispatched in response to the 9:37 a.m. call reporting a gas line had been hit. 

“At this time, there is no explanation for the gap between the first reported gas odor received at 9:11 a.m. and the time that passed before the contractor’s call to 911,” the city statement reads. “While our investigation is ongoing, an initial review of the actions of Engine 1 responding to the first report of a gas odor followed appropriate procedures, and showed diligence in attempting to verify the presence of a gas odor. This investigation is ongoing and a more detailed summary will be provided when the investigation is complete.”

The city does not track reports of gas leaks or reports of gas odor, which “are common emergency calls in the city.” Identifying the source of a leak and shutting it off falls under the purview of Dominion Energy, the city said. Crews from PSNC, which is owned by Dominion, shut off the gas at 11:10 a.m., after an employee was injured trying to shut it off. 

Inspectors from the pipeline safety division of the North Carolina Utilities Commission are investigating how the natural gas line was ruptured.