Taiwanese authorities have arrested the developer of a building which collapsed, killing 39 people.

The developer was arrested on suspicion of negligent homicide, according to local police sources. 

The building collapsed after a 6.4-magnitude earthquake struck the southern city of Tainan around 4am local time on Saturday.

Some 170 people were rescued but the city's mayor said he expected the number of fatalities to be more than 100. 

An eight-year-old girl was pulled alive from the wreckage more than 60 hours after it collapsed.

One survivor spoke of how he propped himself against a wall for 20 hours, wedging himself into a space to avoid falling and smothering her.

Ko Ching-chung said: "Toward the end, to tell you the truth, I had already given up.

"I had no strength left to hold myself up anymore. My body fell on top of her. She would have soon not been able to breathe. I said to her I had to lay on top of her, and she said to me it's OK."

Miraculously, rescuers heard the woman's voice soon afterwards and the pair were pulled from the rubble.

Also among the survivors was 8-year-old Lin Su-chin, who was rescued on Monday along with her 28-year-old aunt, Chen Mei-jih.

By Tuesday, the little girl was well enough to speak to her father and grandparents and say what she wanted to eat. 

"I want to eat gelatin, ice cream - I want to eat so many things," she said.

Tainan mayor William Lai has now ordered rescuers to remove giant concrete slabs with diggers and extractors to hurry up the process and try to find further signs of life.

"It's approaching the 73rd hour and relatives are getting more anxious as time passes by and expect more. They hope the rescue team can make further moves," he said at the scene on Tuesday.

One woman said she was losing hope after three days of waiting for news of her relatives. 

"My brother and sister-in-law are trapped in Building A at the bottom of the wreckage. I feel like they've given up on them," she said. 

"I've been waiting since Saturday in freezing weather at night and I have blankets, how are they going to survive buried down there?

"I'm losing hopes and losing faith in the rescue. If there's no miracle of them coming out alive, I only hope they had passed away quickly and hadn't suffered long."

(Sky News)