Stores and other businesses closed for several hours Friday after customers complained of smelling a strong odor within Westfield UTC.
San Diego Police and San Diego Fire-Rescue were called to La Jolla Village Drive and Executive Way just before 10 a.m. for a natural gas leak.
Construction crews were working in the area when they broke a pipeline, officials told NBC 7.
A bank and more than a dozen stores closed after customers complained of a strong odor.
Firefighters walked through the mall using special detectors but never found any signs of measurable gas.
The leak was successfully capped without any damage or injuries and at 1:45 p.m., fire officials were preparing to reopen the mall.
Westfield UTC used to be known as University Towne Centre and includes such anchor store as Macy's, Sears, Nordstrom and Forever 21.