A 59-year old man has been arrested by police on suspicion of sending malicious messages via Twitter and email to Louise Mensch, a Conservative MP on the committee that recently interviewed News International owner Rupert Murdoch.

The arrested man, who lives in Gloucester, allegedly sent threatening emails to Mensch - also a bestselling author known under her maiden name Louise Bagshawe - about her children. He remains in police custody.

The motive for the threatening messages is not known. Mensch claimed they were from hacking groups LulzSec and Anonymous, though no link has been publicly established. Mensch had called for social networks to be shut down during riots, leading observers to question if this played a part.

Earlier this week, Mensch wrote on Twitter: "Had some morons from Anonymous/Lulzsec threaten my children via email. To those who sent it; get stuffed losers."

Mensch said those sending her messages had "threatened" her to "get off Twitter".