In each question, the first and the last sentences of the passage are numbered S1 and S6 respectively. The rest of the passage is split into four parts. These four sentences are jumbled. Read the sentences and identify their correct and logical order.

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S1: This is the story of a tram that woke up at dead of night and went off on a trip all by itself to end in a disaster.
P: In the early morning of 19 January it suddenly started backing out of the depot on its own.
Q: Tramways sources explained that power supply to the overhead wires at the siding had been switched off for some repair work.
R: It went up a quarter mile away, crashed into state bus which caught fire went it smashed into an electric feeder box and a water tap.
S: There was presumably, some defect in the reversal handle of the tram and its main switch had not been put off.
S6: As a result, when the power supply was restored in the early morning the tram began to move.
The Proper sequence should be: