A fire has torn through at an apartment in southern Seoul, killing four family members, police and fire officials said Friday.

The blaze erupted at around 10:50 p.m. on Thursday on the third floor of the apartment in the affluent Gangnam district before being put out 20 minutes later, they said.

The officials said three people were found dead when firefighters arrived at the scene, while a fourth person was rushed to a nearby hospital where she was pronounced dead.

Three severely burned bodies were found in the living room, bedroom and bathroom, according to police.

Only the family's eldest daughter, aged 23, survived, as she was outside when the fire broke out.

No other casualties have been reported.

Police and fire authorities said they are investigating the exact cause of the fire. (Yonhap)