Rory Cellan-Jones
Technology correspondent

The Conservatives have launched a huge Facebook ad blitz over the last 24 hours - about 2,500 in total with Brexit and NHS messages.

They're clearly targeted at key marginals... including Abingdon, Stroud and Bury.

Today Programme
BBC Radio 4

Image source, HM Inspectorate of Prisons

Nick Hardwick, the former head of the Parole Board, has been speaking after it emerged that the London Bridge attacker was a convicted terrorist who had served half of his sentence.

"This is simply not a suitable subject for silly political point-scoring, it's complicated, it needs careful thought," he says.

"And it needs access to all the facts of this case before we determine a response."

He says he believes that "political point-scoring" is "deeply disrespectful to the families and friends of the people who were killed".

But he adds: "I don't know what happened in this individual case but I do know for a fact that the cuts and reorganisation in the prison and probation service have made them much less able to do their jobs and keep the rest of us safe.

"We've neglected the criminal justice system and now the chickens are coming home to roost."

His comments come as the father of Jack Merritt, one of the victims killed in the London Bridge attack on Friday, further criticised some of the debate around prison sentences last night.

David Merritt previously said his son “would not wish his death to be used as the pretext for more draconian sentences or for detaining people unnecessarily”.

Last night on Twitter, Mr Merritt shared a tweet, external showing some of Monday’s front pages - reporting on the pledges for tougher justice - and wrote: "Don’t use my son’s death, and his and his colleague’s photos - to promote your vile propaganda. Jack stood against everything you stand for - hatred, division, ignorance."

Conservative leader Boris Johnson appeared on the BBC's Andrew Marr show on Sunday.

He again refused to commit to an interview with our colleague Andrew Neil, who is interviewing other political leaders in the run-up to the election.

And the prime minister tried hard to distance himself from his party's years in office, says the BBC's deputy political editor John Pienaar. Read more from John here.

You can also read Reality Check's verdict on some of the claims made in the interview.

Today Programme
BBC Radio 4

At the weekend, Facebook deleted a Conservative Party election ad that used BBC News footage because it infringed the corporation's copyright.

The Tories had rejected a request from the BBC's lawyers to remove the 15-second video but, after the BBC complained to Facebook saying the footage was being used out of context, the social media giant deleted the ad.

Sam Jeffers, the co-founder of Who Targets Me which campaigns for more transparency on internet use in elections, says Facebook's rationale for taking the ad down was not for ethical reasons but "on a copyright basis".

Mr Jeffers, who worked as a social media consultant for Labour in the 2015 election, adds: "Facebook has said that for this election, and all political advertising in general, that it's not going to sort of make judgement calls around the content of advertising.

"So there's no fact-checking, they're not going to take things down based on misleading claims, all of that content is fair game and it's essentially up to journalists to evaluate it."

He says all parties need to agree what is democratically responsible, adding: "One of the problems here is in the absence of rules we end up talking about the rules rather than the issues."

Labour says nationalisation - which it plans to achieve within five years of coming to power - will allow fares to be capped and improve the reliability of services.

It also says it will make it possible to greatly simplify the ticket system.

Looking at the other parties for a moment...

• The Conservatives are calling Labour's policy "another desperate attempt" to "distract" people from tax rises and Brexit uncertainty they claim a Corbyn goverment would bring. The Tories themselves are pledging to improve transport links and reverse cuts to the railway network made in the 1960s.
• The Liberal Democrats have pledged to freeze peak-time and season ticket train fares for the next five years and cancel the 2.7% rise in rail tickets from 2 January 2020. They also plan to complete the HS2 high-speed rail link.
• The Brexit Party's flagship transport policy is scrapping the HS2 rail project - a goal it shares with the Green Party.

Katie Prescott, Business reporter, BBC News

In keeping with their proposals to nationalise the railways, Labour's plans to significantly cut fares would see a reverse in the direction of travel for policies on train fares since privatisation.

Since 1995, successive governments have tried to move the day-to-day cost of running the railways onto fare-payers and away from the taxpayer. At that time, it used to be split 50/50 - now it's more like 75% on the shoulders of the passenger.

The argument goes that by raising fares in line with the Retail Prices Index inflation figure each year, government spending on the railways can be reserved for investment in infrastructure.

Announced just two days after the average train fare rise of 2.7% was published, and coinciding with major industrial action on several lines in the run-up to Christmas, Labour's proposal for a significant cut to fares could prove popular with commuters.

The future of ticketing and rail fares is just one of the issues being looked at by a major review into the UK's railways due to report after the election.

It is led by Keith Williams, the former boss of British Airways, who is particularly interested in how innovation in aviation fares and ticketing could be applied to the railways.

Lots on the schedule for Monday - here's a rundown for you:

• Conservative leader Boris Johnson will start off campaigning in the south of England before heading to a rally in the east of England this evening. The Tories are promising to improve the UK's border security if they get elected, by introducing automated exit and entrance checks and making it harder for people with serious criminal convictions to enter the UK from EU countries
• Meanwhile, Labour leader Jeremy Corbyn will be in London to talk about rail policies. The party has announced plans to slash rail fares by 33% and simplify ticket prices for part-time workers if it wins the election - as well as making train travel free for under 16s
• In Glasgow, Scottish Labour leader Richard Leonard will be campaigning
• The Lib Dems' justice spokesman, Phillip Lee, will visit a mental health initiative in London to talk about his party's plans for investment in the sector
• Meanwhile, Brexit Party leader Nigel Farage will campaign in north Wales.
• Scottish National Patry leader Nicola Sturgeon - who will be taking part in a live Q&A session on BBC Radio 5 Live and the BBC News channel later - will warn that rural Scotland is among the areas most at risk from a bad Brexit deal as she visits Lockerbie
• And we have the final two manifesto launches of the campaign - Sinn Fein will unveil theirs in Londonderry, while UKIP will do the same in London

As the policy announcements continue to flow from the parties desperate to win your vote, we're pulling them all together into one key guide.

Read it here.

Welcome to BBC News’ live coverage of day 27 of the general election campaign, ahead of polling day on 12 December.

Parties will resume campaigning today, after Friday’s attack on London Bridge.

Last night, leading figures from the UK’s political parties clashed on some of the key election issues in an ITV debate. Read about what happened during the debate here.