If you follow any Labour politicians or activists on Twitter, the odds are your timeline was briefly flooded with identical messages posted at exactly the same time.

They haven't all done this manually. Labour has been experimenting with a tool called Thunderclap to spread its message on social media.

Last week more than 800 people agreed to let Labour control their Twitter account – for this one-off tweet.

The Conservatives have previously asked their MPs to tweet the same attack lines. But that's been done manually.

Both approaches risk annoying people.
8 tweets in a row on my feed from Labour people using identical wording about freezing energy bills. Must be dalek day.
Jack Grimston
@GrimstonJack
8 tweets in a row on my feed from Labour people using identical wording about freezing energy bills. Must be dalek day.
Just received 8 identical tweets in a row from Labour supporters calling on Cameron to freeze power bills. I get the message, comrades. . .
David Carter
@Manxstar
Just received 8 identical tweets in a row from Labour supporters calling on Cameron to freeze power bills. I get the message, comrades. . .
@thedancingflea It filled up my timeline with scary robot-people...
Caroline Crampton
@c_crampton
@thedancingflea It filled up my timeline with scary robot-people...