MTR services on the Tsuen Wan Line were back to normal on Monday morning after a day of chaos on the line following a train derailment at Yau Ma Tei on Sunday.

The MTR Corporation confirmed that trains would run the full length of the line from 5.50am after engineers worked through the night to fix problems on the track at Yau Ma Tei station. The stricken train was taken to the depot at Tsuen Wan.

The government has ordered an investigation of Sunday morning's incident at Yau Ma Tei, in which several carriage doors came off the train. MTR officials say they suspect the bogie of the first carriage came "slightly" off the rail.

One passenger required hospital treatment for abrasions.

Louis Szeto, chairman of the international strategy board of the Institution of Mechanical Engineers, said the incident could have been more serious had it not been for the driver hitting the emergency break repeatedly.

He said attempting an abrupt stop could have sent the train crashing into platform screens or caused train doors to fly into the carriages.