Two sons of a man shot by immigration officers in Houston testified at a congressional hearing Friday, describing the horror and confusion of learning their father had been killed and demanding a transparent investigation into how he died and why.

Lorenzo Salgado Araujo was killed July 7 when Immigration and Customs Enforcement officers chased his white work van through the streets, then shot him through the window in front of his work crew, including his brother.

Salgado Araujo's sons read from prepared remarks at a Houston hearing with Democratic members of Congress.