SINGAPORE - Two men were taken to hospital for smoke inhalation after a fire broke out in a flat in Yishun on Sunday morning (June 24).

The Singapore Civil Defence Force (SCDF) said it was alerted to the fire in the fourth floor unit at Block 663 Yishun Avenue 4 at around 7am.

Some 100 residents living in units up to the 12-storey block's top floor were evacuated as a safety precaution.

A 16-minute video posted by Facebook user Dahlia SenSasi shows dense grey smoke billowing from the unit into the corridor and to the flats above.

Bright, orange flames could be seen inside the unit, as firefighters arrive at the scene.

SCDF said that two fire engines, a Red Rhino, two fire bikes, an ambulance and three support vehicles were dispatched to the scene.

The fire involved contents in the flat's living room, kitchen and two bedrooms, SCDF added.

Firefighters put out the flames using two water jets.

Two men in their 20s, who live in the unit, evacuated before SCDF's arrival. They were taken to Khoo Teck Puat Hospital for smoke inhalation.

Radiographer Sim Yan Yi, who lives on the 10th floor, was among those who were awoken from their sleep and had to be evacuated from their home.

The 25- year-old told The Straits Times that she heard an explosion at about 7am, but initially thought it was just an accident at the carpark.

"I didn't think too much about it until I noticed an acrid, burning smell about five minutes later," she said.

"The corridor to my unit was filled with white smoke and it got a little difficult to breathe. My eyes were also stinging."

She added that a neighbour who lives on the same floor as her went around knocking on doors to inform residents about the fire.

A large crowd of people had already gathered at the foot of the block when she evacuated at about 7.15am, she said, adding that she was allowed to return to her flat at around 9am.

Nee Soon GRC MP Muhammad Faishal Ibrahim said he was about to take his daughter to Changi Airport for her flight when he received a call from a resident about the fire.

In a Facebook post, he said that he was briefed by SCDF and police about the situation upon arriving at the block and also spoke to the affected residents.

He thanked the SCDF and police for their help, and added that the relevant agencies and community organisations will be assisting needy residents.

"It was a big fire and they had worked very hard to put our the fire," he added.

Investigations into the cause of the fire are ongoing.