Four Americans remain missing in Mexico.

We'll also look at a new report on air pollution.

I'm Jeff Pierre and this is the seven from the Washington Post. It's Tuesday March 7th.

Let's get you caught up with today's seven stories.

First up, an update from Ukraine. The fight over Bachmoot has intensified. The city in eastern Ukraine is the biggest flashpoint between Russia and Ukraine right now.

President Velodimir Zilinsky said last night that point between Russia and Ukraine right now.

President Velodimir Zilinsky said last night

that Ukraine will not retreat from Bakmut,

even though Russian forces have nearly surrounded it.

The city itself holds little strategic significance, but capturing it would give Russia a symbolic win after months of setbacks. Number two, four U.S. citizens have been kidnapped in Mexico.

This happened on Friday in the city of Matamoros,

which is across the border from Brownsville.

That's a city in Texas.

Mexican President Andres Manuel Lopez-Obrador said that the Americans were caught in a crossfire

between groups.

In a White House briefing yesterday,

press Secretary Corinne Jean-Pierre

explained how U.S. law enforcement is trying to bring the four Americans back home.

These sorts of attacks are unacceptable. Our thoughts are with the families of these

individuals and we stand ready to provide all appropriate consular assistance.

U.S. law enforcement is in touch with Mexican law enforcement.

The departments of state and Homeland Security are also coordinating with Mexican authorities and we will continue to

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