The police are investigating email threats allegedly made against Conservative MP Louise Mensch's children by hacking groups Anonymous and LulzSec.
A spokesman for the Metropolitan Police told the BBC that investigators were examining an email sent to the MP. Mensch sat on the parliamentary committee that questioned Rupert Murdoch and his son James over phone hacking at News International.
After the UK-wide riots Mensch also called for Twitter and Facebook to be temporarily closed during similar outbreaks of violence.
Mensch is an avid Twitter user herself and revealed receiving the email under investigation by police on that social platform, although not the exact contents of it.
In her tweet, she said: "Had some morons from Anonymous/Lulzsec threaten my children via email. To those who sent it; get stuffed losers.
"I have contacted the police via the House of Commons and the email is with them now. I am posting this on Twitter because they threatened me to get off Twitter."
The Anonymous hacking group has picked targets it believes curtail free speech online and LulzSec has used its attacks to expose poor online security on corporate websites.
A Scotland Yard spokesman said: "We can confirm the Met has received an email this morning making allegations of malicious communications."