The father of Alfie Evans has said his seriously ill son has been “failed disgracefully by the system” after losing a last-ditch legal challenge at the European court of human rights.

Alfie, who is 22 months old, has a rare degenerative brain condition and has been at the centre of a life-support treatment battle.

His parents, Tom Evans and Kate James, from Liverpool, asked judges at the ECHR to examine the case after they exhausted all legal avenues in the UK.

On Wednesday, judges in Strasbourg rejected the case and said they had found no appearance of any human rights violation.

Tom Evans and Kate James, Alfie’s parents. Evans posted on Facebook that the ruling had left them ‘in bits, distraught, in pain’. Photograph: Philip Toscano/PA

Writing on Facebook after the ruling, Evans said he and his partner were “in bits, distraught, in pain”, and the decision meant their son was “about to be murdered”.

Judges at the high court and supreme court in London previously heard that Alfie, who was born on 9 May 2016, was in a semi-vegetative state and had a worsening neurological condition that doctors had not definitively diagnosed.

Specialists at Alder Hey children’s hospital in Liverpool, where the toddler was being treated, said life-support treatment could stop and high court judges accepted medical evidence that showed further treatment was futile.

In a message to supporters after the Strasbourg ruling, Evans posted pictures of Alfie on his bed at Alder Hey, dressed in pyjamas and with a dummy in his mouth and holding his father’s hand.

He wrote: “Failed disgracefully by the system. Does our son look in any of these pictures like he is dying!!!!!”

Evans said: “We as parents are not giving up … Our son is about to be murdered, taking [sic] away from us, his innocent life is about to be taken.

“Please our Queen, Pope Francis, please Angela Merkel. Someone save our innocent not dying son. He looks into our eyes every day, he responds to us every day. Alfie James Evans we love you so so so much. We will do everything we can.”

In a message directly to Alder Hey, Evans added: “Please AH let him go home to die on a [tracheotomy] that he can pay for out of his own funds!!! We beg now [Alder Hey] to work with us.”

In a statement, Alder Hey said it would work with Alfie’s parents to “agree the most appropriate palliative care plan” for the child.

It added on Wednesday night: “Today the European court of human rights declared Alfie’s family’s application inadmissible, finding that there was no appearance of a violation of the rights and freedoms set out in the European convention on human rights. This signals the end of a very difficult and protracted legal process.

“We understand that this decision is very distressing for Alfie’s family. Our priority is now to work with them to agree the most appropriate palliative care plan and we would ask that their privacy is respected at this time.”