( CNN ) -- A fire at a karaoke bar and discotheque in Medan , in Indonesia 's North Sumatra province , killed at least 20 people Friday night , according to a hospital . At least two people survived , according to Aida Sofiati of the Pringadi Hospital in Medan . Sofiati said 20 people were killed . Mohammad Zein , a fire official , said the blaze started around 10 p.m. , but firefighters were able to extinguish it within a half-hour . He said the cause of the fire was not known .
Blaze hits karaoke bar and discotheque in Medan , in North Sumatra province . Score: 7 Fire official : Fire started around 10 p.m. , was extinguished within half-hour ; cause is n't known .