HOUSTON -

Since Friday's deadly fire at a southwest Houston hotel, cars have slowed down to see the damage.

As of Sunday evening, three of the dozen injured were still in the hospital. One of them was listed in critical condition.

There's a makeshift memorial in front of the burned Southwest Inn. It's in honor of the four fallen firefighters, Captain Matthew Renaud, Engineer Operator Robert Bebee, firefighter Robert Garner, and the youngest firefighter, Anne Sullivan.

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The four firefighters all went in to make sure no one was trapped inside the massive 5-alarm fire on Friday. The building collapsed, trapping them inside.

Sunday morning, ministers and pastors, firefighters and their families held umbrellas, Bibles and prayed in the rain for those injured and those grieving.

The investigation into the deadly hotel fire has started. Nearly 50 investigators from five city, state and federal agencies began sifting through the scene Saturday morning.

Arson investigators are asking that anyone who may have witnessed Friday's fire to call them at 713-247-8900.