- Christiane K is suspected of poisoning her five children at their home in Solingen
- Police sources said her eldest child, 11-year-old Marcel, saw the killings unfold
- She then took him away on a train before getting out and jumping on the tracks
- The mother survived with serious injuries while the boy went to his grandmother
- Police are awaiting results of toxicological tests on the dead children aged 1 to 8
An 11-year-old boy allegedly witnessed his five brothers and sisters being killed by their mother before she tried to take her own life in Germany.
Christiane K, 27, is suspected of poisoning the five children whose bodies were discovered at an apartment block in Solingen on Thursday.
Police sources told RTL that the surviving eldest child, 11-year-old Marcel, saw the killings unfold before his mother took him away on a train.
After arriving in Duesseldorf, the mother got out and jumped on the tracks, but survived with serious injuries while the boy was sent to his grandmother.
The five dead children were three girls aged one, two and three, and two boys aged six and eight.
According to Bild, Marcel's younger brothers were called Luca and Timo, while the three young daughters were Sophie, Leonie and Melina.
Police have made contact with the children's father, it is believed, after forensic officers scoured the apartment building on Thursday afternoon.
In 2014, the mother told her social media contacts that she had 'lost the love of her life' - before suffering a further personal crisis when her apartment burned down.
However, the motive for the alleged killings is not known and police said it was too early to speak about it.
One criminologist warned that possible warning signs might have gone unnoticed because of the pandemic and resulting lockdown.
Police said they were alerted by the children's grandmother in nearby Moenchengladbach, who had recently been in contact with the mother.
'We were informed shortly before 2pm that five children had died and this has unfortunately been confirmed,' police spokesman Stefan Weiand said.
'At the moment we believe that the 27-year-old mother appears to be responsible,' he added.
The mother was not at the apartment when they arrived at the scene, they said. She is now in hospital but not yet in a fit state to speak to police.
Asked about reports that medication was involved in the children's deaths, Weiand said: 'We are investigating in that direction.'
Rescuers themselves were said to be traumatised by what they found in the building, and also shocked by the state of the flat.
One report said that rescuers had tried to resuscitate the children but arrived too late to save their lives.
Detectives are now awaiting the results of toxicological tests on the children, who did not have any visible injuries.
After leaving the apartment, 11-year-old Marcel travelled with his mother to Duesseldorf and continued on alone to his grandmother in Moenchengladbach.
It is unclear whether he witnessed his mother's suicide attempt.
The woman was rescued from between two track beds and taken to a local hospital for treatment, emergency services said.
German railway operator DB said there were temporary closures in Dusseldorf because an emergency doctor had been needed on the track.
Several police officers could be seen around the apartment building in the early evening, along with ambulances and police vehicles in a cordoned-off area.
Police said more than 40 officers were dispatched to the scene.
'The family tragedy in Solingen fills me with great sadness and at the moment my thoughts and prayers are with the five small children whose lives were snatched from them so terribly early,' said Herbert Reul, interior minister for the state of North Rhine-Westphalia.
Tim Kurzbach, the mayor of Solingen, said: 'I am shocked and deeply saddened by the news that five dead children have been found in our city.'
Solingen is a city of 160,000 people around 20 miles from Duesseldorf and Cologne.
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