About 4,000 Entergy customers lost power Saturday afternoon in Little Rock's downtown and areas south of downtown between Interstate 630 and Interstate 30, according to the utility's spokesman David Lewis.
Lewis was not sure what caused the outage but said problems began at 4:11 p.m. at the substation at 23rd Street and Spring Street.
"I wish I knew what happened in that substation, but usually we don't," Lewis said. "Sometimes it's just a random piece of equipment fails."
Crews were working into the evening to reroute lines to get power restored to as many customers as possible.
"We are in the process of doing some switching to get some of the customers back on as quickly as we can," Lewis said. "With all these lines and the routes that they follow, sometimes you can route the power around the thing that's malfunctioning."
The utility's online outage map showed that power had been restored to all but a few places downtown as of 7 p.m. Saturday.