A fire tore though a nursing home in southeastern South Korea on Friday, killing 10 people and injuring 17 others, police said.

All of the victims were women in their 70s or older who were sleeping when the fire broke out in the early morning on the first floor of a two-story building in the port city of Pohang, police officer Lee In-shik said.

He said 17 people sustained minor injuries and were taken to nearby hospitals for medical treatment.

The fire raged for about 30 minutes before firefighters put it out, he said. Police and fire officials were trying to determine its cause.

President Lee Myung-bak expressed regret about the deaths before heading into the venue of the Group of 20 summit of major economies under way in Seoul, according to his spokeswoman Kim Hee-jung.

Pohang, home to South Korean steelmaker Posco, is about 230 miles (370 kilometers) southeast of Seoul.