A power outage left over 19,000 customers without electricity Saturday afternoon, according to the Lansing Board of Water & Light's outage map.

BWL CEO Dick Peffley said the utility was performing routine testing at its Eckert substation when the entire substation tripped, cutting power a little after noon for thousands of customers, mostly in south Lansing.

As of 1:30 p.m., the outage map listed 18,606 customers without power.

Peffley said BWL will conduct an in-depth review next week to determine the cause of the issue. All outages had been restored by 1:45 p.m.

Contact reporter Annabel Aguiar at aaguiar@lsj.com. Follow her on Twitter @annabelaguiar.