HOUSTON - Five people, including four children, were killed in a house fire Wednesday in the US state of Oklahoma.

Seven people were inside the home in Oklahoma City when the fire broke out just before dawn on Wednesday morning, the news website NewOn6.com quoted fire chief Randy Cornelius as reporting.

Cornelius confirmed five people dead, including four children ages two to eight. The fifth victim was an adult woman.

One person was taken to the hospital, while another victim at the scene refused treatment. ?All victims were related.

Crime scene investigators were on the scene, according to the report. The cause of the fire was under investigation.