Jill Disis

jill.disis@indystar.com

First the lights flickered.

Then came the boom.

"I looked out my window on the fourth floor and saw smoke rising up," Mark Neyland said.

Neyland and hundreds of other people were evacuated from restaurants and at least one entire office complex along a busy stretch of Meridian Street in Downtown Indianapolis on Wednesday after an underground explosion involving Indianapolis Power & Light Co. equipment.

The incident closed a stretch of Meridian Street as fire crews and IPL officials investigated the blast that filled the air with heavy brown smoke

IPL had restored power by 8 p.m. Wednesday by switching the businesses to a different power source, spokeswoman Brandi Davis-Handy said. The company's engineers will begin examining the explosion Thursday to determine why it happened.

The first blast occurred about 1:30 p.m. near 100 S. Meridian St., between Washington and Maryland streets. Neyland, who works for the Indiana Housing and Community Development Authority in its 30 S. Meridian St. office, said that blast was quickly followed by dozens of "mini-explosions." Firefighters who had gone inside flooded back out, he said.

"I mean, it was just boom, boom, boom, boom, boom," he said, "and then they cleared the entire block."

Authorities said no one was injured, but the explosion's aftermath continued to cause problems for several businesses along Meridian Street, including Oceanaire Seafood Room, Napolese Pizzeria, Kite Realty and Carson's department store. All of those businesses are expected to be without power Wednesday.

Indiana Supreme Court Chief Justice Brent Dickson also authorized state court administration employees working in offices at 30 S. Meridian to go home for the day because of the evacuation of the building. Computer servers in the appellate court data center had to be shut down.

Brandi Davis-Handy, spokeswoman for IPL, said the power outages were necessary so IPL workers could make repairs.

What exactly happened is still unclear. Davis-Handy said IPL officials traced the problem to the failure of an underground network protector, which she described as similar to a "really big circuit breaker."

The Indianapolis Fire Department initially described the incident as "a series of small transformer explosions." IPL owns a vault that holds four transformers at 26 S. Meridian, which feed into the northeast side of Circle Centre mall.

Davis-Handy said that wasn't accurate.

"There's definitely no evidence of a transformer explosion," Davis-Handy said. "It's a fairly large vault. Each transformer is housed in a separate room within that vault, so they're actually very protected."

IPL came under scrutiny for a series of underground explosions in 2010 and 2011 that prompted the state's utilities regulator to examine how IPL maintains its underground equipment. Those instances damaged cars, scorched buildings and sent manhole covers soaring into the air, sometimes just a few feet from customers dining on patios.

IPL later said it locked down 150 of its manhole covers Downtown. The Indiana Utility Regulatory Commission also asked IPL to fix three areas where leaks from underground steam pipes were occurring close to its buried electrical cables.

Davis-Handy said it's "definitely too early to say" whether this incident is related to those troubles but added that "those were manhole incidents, and this is not a manhole incident."

Call Star reporter Jill Disis at (317) 444-6137. Follow her on Twitter: @jdisis.