About 46,000 New York City customers were blacked out as of 9 p.m. Sunday because of continued heat and high usage, just one week after a transformer fire led to a massive outage for nearly 75,000 people.

The majority of Sunday's blackouts affected the boroughs of Brooklyn and Queens, reports Yahoo News.

NYC Mayor Bill de Blasio tweeted about the outages, saying "accumulated heat and strain from the past few days has built up in the electrical equipment."

"I just spoke to Con Ed's president about tonight's outages. Their system in parts of Brooklyn is under severe strain and some equipment has failed," The Mayor tweeted.

In the meantime, Con Edison tweeted they have restored 10,000 customers in the affected Brooklyn area and are working safely to restore everyone.

Source: Yahoo News, Cone Edison (Tweeter), Mayor Bill de Blasio (Tweeter)