A woman watched as her two-year-old son was hit by a train travelling at 60mph after trying in vain to stop him toddling on to a railway line.
Johnny Hall, who would have been three next month, died instantly after being hit on a level crossing at Peterborough, Cambridgeshire, officers said yesterday.
Police said the little boy – who was from Peterborough – and members of his family had been visiting friends who lived next to the line.
Johnny's aunt, Eileen Connors, said the little boy's death on Monday was a "tragic accident" and no one was to blame.
Police said Johnny toddled down a path toward the crossing and got on the line before his mother – who has not been named – could reach him.
Officers said the little boy's uncle and four-year-old brother were also nearby.
They said investigators were not sure how Johnny had negotiated a metal railing gate and adjoining fence which guarded the line.
Officers said the train driver, who was making his way from Lincoln to Peterborough and carrying about 20 passengers, saw the toddler and honked his horn but could not stop.
Superintendent Paul Brogden said Johnny was a member of the travelling community and had been visiting a traveller site near the crossing.
"It seems that Johnny made his way down the path towards the line and then got on to the crossing and was hit by a train," said Mr Brogden.
"His mother followed him down the path and tried to stop him getting on to the line but to no avail. Tragically she saw the accident and she is obviously distraught."
He added: "At this stage we cannot say how he got past the gate and fence and on to the line. But this would appear to be a tragic accident. There is no suggestion of negligence here."
Police and Department of Transport investigators have begun an inquiry.
Yesterday Ms Connors said the little boy was "loved by everyone who knew him".
Eileen Connors said Johnny's family felt only sorrow and did not blame anyone for his death.
"He's a little boy who was full of life and loved by everyone who knew him," she said.
"We truly believe that Johnny is now a little angel in heaven."
She said Johnny's death had been a "tragic accident" and added: "No blame is placed. Only deep sorrow."
Safety improvements were made to the level crossing where the two-year-old was killed after an inspection in May, health and safety officials said yesterday.
The Office of Rail Regulation (ORR) – which has responsibility for health and safety on railways – said a sliding latch had been altered so the metal railing gate guarding the crossing at Peterborough, Cambridgeshire, could not be fixed shut.
A spokesman said inspectors were concerned that if the latch had to be released before the gate would open, anyone trapped on the crossing would find it harder to escape.
The spokesman said inspectors had advised Network Rail – which operates and maintains tracks and crossings – to remove the latch. Instead, Network Rail had left the latch in place but fixed it in an open position so pedestrians could simply push or pull the gate.He said inspectors had re-checked the crossing following Johnny's death yesterday, found it to be in good working order and remained satisfied that the correct decision had been made.
Police said Johnny had ventured down a path to the crossing and negotiated the gate – and adjoining fence – before his mother could reach him.
They said investigators were not sure how the toddler had got through the barrier and on to the line.
"We asked Network Rail to remove the latch so the gate could not be fixed shut because inspectors were concerned for the safety of anyone on the crossing," said the ORR spokesman.
"They actually kept the latch on but locked it in the open position and we were happy with that."
Network Rail said yesterday that the crossing was in good working order.