Shenzhen in South China's Guangdong province experienced a widespread two-hour power blackout on Tuesday evening caused by a transformer station failure.

Around 8:30 pm on Tuesday, many areas in Shenzhen's Luohu, Futian, Longgang and Yantian districts were plunged into darkness.

The Shenzhen Power Supply Bureau reported Tuesday evening that an initial investigation showed a 500KV transformer station in Longgang district had failed. After emergency repairs, power was restored by 10:10 pm.

The power failure blacked out streetlights and traffic lights. Feng Xinyi, director of the command center of Shenzhen Traffic Police Bureau said 200 traffic policemen were dispatched to man the roads while 23 electric generators were used to power traffic lights at several key intersections.

Traffic lights stop working at Sungang Road in Shenzhen on April 10, 2012.[Photo/CFP]

"The area that traffic lights were out was quite extensive this time. It's been rare in the last few years," he said.

Li Fang, a resident in Futian district, said the power went out when she was cooking.

"I was just about to do the last dish when the lights went out. I had to use my Nokia cell phone as an emergency light," she said. "Luckily the rice in the electric rice cooker was done before the blackout. The blackout lasted around 20 or 30 minutes, and I also had no running water during this time."

Li said a colleague who lived near the KK100 building, told her Shenzhen's tallest building was completely dark.

"She said the blackout lasted so long, she could not wait for the lights to come back on and went to bed very early," Li said.