LANZHOU - Five people have been detained in?Northwest China's Gansu province for their alleged involvement in a mine carriage crash in which 20 miners were killed on Tuesday, local public security authorities announced on Wednesday.

The names of the five, who are suspected of being accountable for the accident, were not given by the public security bureau of Baiyin city's Pingchuan district in Gansu.

It did reveal, however, that one of them is the head of the coal mine.

Twenty people were killed in Qusheng pit in Baiyin early on Tuesday, when a steel cable pulling a locomotive loaded with 34 miners in two carriages snapped.

The carriages slipped and overturned, sending all the workers aboard plummeting into the pit.

An initial investigation suggested the carriages were overloaded

The mine, run by Qusheng Coal Mining Co, was operating illegally, as it was one of 55 mines safety authorities had ordered to halt production for an industrial reshuffle.

Four of the 14 survivors were seriously injured. But a hospital official told media on Wednesday that they are all in a stable condition after medical treatment.

The pit began operating in 2003 and has a designated annual output of 90,000 tonnes.

In the wake of the accident, the provincial government of Gansu has demanded a temporary shutdown of all mines with annual output below 300,000 tonnes for a safety overhaul.