Boy reportedly loses leg after mother pushes him in front of approaching train

According to German media reports, travellers watched as the boy fell onto the tracks at Hamburg's Hoheluftbruecke railway station on Sunday.

The driver was unable to stop in time and the boy's leg was crushed under the wheels.

His mother, known only as 31-year-old Jana, then attempted to flee but was quickly apprehended by police, Germany's Bild newspaper reported.

According to Bild, it took rescue services almost 40 minutes to free the boy, who has been named as 11-year-old Leon, from underneath the train.

He is understood to have remained conscious throughout the ordeal.

Hamburg Police told Sky News the boy remains in a severe condition, but did not suffer life-threatening injuries. They would not comment on local media reports that doctors have had to amputate the boy's leg.

His mother is currently undergoing a psychiatric evaluation amid reports that she is suffering from a psychological condition.