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Good morning.

Here’s what you need to know:

• Powerful quake kills hundreds in Mexico.

Rescue crews are scrambling to pull survivors from the rubble after an earthquake with a preliminary magnitude of 7.1 struck on Tuesday, killing more than 200 people.

At least 21 children died when a school collapsed, and the toll across the country is expected to rise. We mapped the extensive damage in Mexico City, and have video from the moment the quake hit.