(SANDUSKY) — Electrical service for 2,100 customers in the Sandusky area was interrupted Sunday due a failure at the Sandusky DTE substation. The outage occurred shortly after 7 a.m. 800 residents were back online around 9:30 a.m.; however, the area west of M-19, including the Westpark business area, was without service for most of Sunday. The power interruption is believed to have been caused by a squirrel or bird that became entangled in one of the transformers.