The number of domestic violence killings has hit a five-year high, new figures show.Data obtained by the BBC from 43 police forces across the UK reveal that 173 people died in domestic violence-related homicides last year.

The statistics, reported on Friday, show there were 165 domestic killings in 2014, 160 in 2015, 139 in 2016 and 141 in 2017.

One criminologist, who anonymously talked to the BBC, described those killed as "invisible victims of knife crime".

The new data emerged after Prime Minister Boris Johnson pledged to reintroduce domestic abuse legislation in the next Queen's Speech.

Mr Johnson tweeted on Thursday: "Domestic abuse shatters lives and tears families apart.

"We are fully committed to tackling this horrific crime - which is why the Queen's Speech will confirm we will be reintroducing domestic abuse legislation in the next session."

Sir James Munby, former president of the Family Division of the High Court of England and Wales, has called for the Domestic Abuse Bill to be brought back before Parliament.

He told BBC Radio 4's Today programme on Thursday: "This is a vitally important Bill, tackling what everyone agrees is a very great social evil.

"It is immensely depressing nothing effective has been done to get this necessary reform through Parliament."