HOUSTON (AP) - Investigators say an early-morning fire at an apartment complex in Houston left four people dead, including two children.

The cause of Friday's fire is sought.

Assistant Fire Chief Kevin Alexander says firefighters entered the ground-floor unit and found two victims, then discovered two more. The victims were two adults and two preschool-age children.

Authorities say the four victims, all from one apartment, were transported to Houston hospitals, where they were pronounced dead.

No firefighters were hurt. Arson investigators were called to the scene.

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