Media playback is unsupported on your device Media caption Stella Creasy and Toby Young debate how best to deal with Twitter trolls

The Scottish police force has apologised for a tweet sent during a Newsnight debate about abusive messages on Twitter.

The tweet mocked columnist Toby Young's contribution to the programme. It was later deleted.

Police Scotland said the matter was being investigated and Twitter access was being reviewed.

Mr Young said he had blocked the force's account, was not offended and would not complain.

The journalist was appearing in a discussion with Labour MP Stella Creasy.

Blocked account

Ms Creasy, who has received threats of rape on Twitter, wants social networks to do more to protect users and to identify perpetrators.

This debate over internet abuse - known as "trolling" - began when Caroline Criado-Perez was bombarded with abuse via Twitter after successfully campaigning to have author Jane Austen depicted on the new £10 note.

Image caption Police Scotland said it was sorry for any upset caused by the incident

Ms Creasy appeared on Newsnight with Mr Young on Tuesday night.

The MP told the programme: "We need to make sure that police at a local level and at a national level understand the risks and dangers that can come from online behaviour."

Mr Young, who writes for the Daily Telegraph, argues that blocking and ignoring abusive posters on the internet is sufficient "in 99 cases out of 100".

A tweet on the Newsnight debate sent from the official Scottish police account contained an insult directed towards Mr Young [@toadmeister].

After receiving the message, he responded: "Just had to block @policescotland, the official police Scotland twitter feed, for abusing me on twitter. This is getting weird"

On Wednesday morning, Police Scotland tweeted: "We apologise for the tweet sent to @toadmeister & for any upset caused. The matter is being investigated & we're reviewing Twitter access."

In a blog on the incident for the Telegraph, Mr Young said he had asked the Scottish force not to take any action against the person responsible, who had probably confused a personal account with a work one.