A fire tore through a karaoke bar in southern Vietnam killing 12 people and leaving 11 injured, a local official said Wednesday.

The blaze engulfed the second and third floors of the building on Tuesday night, trapping customers and staff members as dense smoke filled the staircase, state media reported.

Many crowded onto a balcony to escape the flames, which grew quickly as they caught the wooden interior, and others were forced to jump from the building, the reports added.

Photos showed plumes of smoke billowing out of the bar -- located in a crowded residential neighbourhood in Thuan An city, north of commercial hub Ho Chi Minh City -- as firefighters on cranes tried to extinguish the fire.

A local official confirmed to AFP that 12 people were dead and 11 injured in the blaze.

"Rescue teams are still looking for victims at the scene. The cause of the fire has not been determined and is being investigated," Nguyen Thanh Tam, a top official with the ruling communist party in Thuan An city, told AFP.

Witness Nguyen Sang, who lives near the karaoke bar, told the VnExpress news site that when fire trucks arrived at the scene, a receptionist said there were 40 people stuck inside.

"Many people ran outside through the main entrance, but many others could not stand the heat and they jumped down, breaking their hands and legs," Sang said.

The fire was Vietnam's deadliest since 2018, when 13 people died in a blaze in an apartment complex in Ho Chi Minh City.

In 2016, a blaze in a karaoke bar in Hanoi left 13 people dead, prompting a country-wide assessment of fire prevention measures at bars and clubs.

Last month, three firefighters died after trying to extinguish a fire at another karaoke bar in the capital city.