LONG BEACH (AP) — Port of Long Beach businesses have been cleared to use their water again, two days after routine tests revealed water contaminated with black crude.

The contamination was discovered Wednesday in the water main as port workers opened and flushed fire hydrants to make sure they were working.

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Various businesses including restaurants and hotels were advised not to allow their employees or guests come in contact with the contaminated water.

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Port spokesman John Pope says water at the port’s administrative office building will remain shut off as officials continue to investigate the cause.

No health complaints have been reported.

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