Facebook restricts violent video clips and photos

Facebook has begun placing warnings over videos posted to its site, stating their contents might "shock, offend and upset" if viewed.

The alerts prevent the videos from automatically playing in feeds unless they are clicked, unlike other clips.

The site is also preventing graphic videos and photos from being shown to any user who has identified themself as being under 18 years old.

It follows pressure for the move from its own safety advisers.

But one psychologist said the measure still did not do enough to protect young, vulnerable members of the social network.

Among the first posts to be affected are uploaded files containing video footage of policeman Ahmed Merabet being shot dead in Paris by a terrorist involved in last week's Charlie Hebdo attacks.