If your lights went out and your morning routine got off to a rough start on Monday, you weren’t alone.

According to NBC10 Boston, more than 10,000 Eversource customers lost power early Monday morning in a widespread outage that impacted parts of Boston, includingSouth Boston. Some traffic signals were also affected as crews worked to restore service.

Eversource initially reported that the outage was caused by an issue with underground equipment just before 6 a.m. However, after further investigation, the company determined the problem originated at the Andrew Square substation.

Power was gradually restored throughout the morning, with all affected customers back online by 8 a.m., according to Eversource.