HAVERHILL (CBS) – Thousands of residents and businesses could be in the dark in Haverhill over the next few days. National Grid says Haverhill was one of the hardest hit cities after the latest Nor’easter.

As of Thursday afternoon, 70 percent of Haverhill had no electricity. An estimated 100,000 customers in the Merrimack Valley are without power and may have to wait a few days for it to be restored.

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Cordi O’Hara, the President of Massachusetts National Grid, is asking for customers to be patient because she says safety must come first.

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There are hundreds of fallen trees that have brought down power lines and those situations must be first assessed for safety, then assessed for damage and cleaned up before restoration begins according to O’Hara.

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Statewide, more than 250,000 residents were still without power Thursday night.