A man sent racist and threatening emails to six MPs, including one which urged David Lammy to “remember what happened to Jo Cox”.
David William Hall, 72, of Wolverhampton admitted six counts of sending grossly offensive messages.
Emails were also sent to MPs Dominic Grieve, Anna Soubry, Nicky Morgan and Heidi Allen.
Hall, who also sent a email to Eleanor Smith calling for her to be put on a “banana boat”, will be sentenced later.
Former education secretary Ms Morgan said the “threats of violence or death” crossed a line.
‘Burn in hell’
Ukip supporter Hall sent the emails last December, in the wake of a Brexit debate in parliament, the court heard.
One email, littered with capital letters and exclamation marks, was sent by Hall to four of the MPs after a parliamentary vote on an amendment to the EU Withdrawal Bill.
It had in the subject line: “Your back stabbing treachery” and read: “You deserve to be HUNG for your attack on our democracy yesterday.”
The email concluded, in capitals: “May you burn in hell for eternity.”
Prosecutor Matthew Brook said an email to Wolverhampton MP Eleanor Smith was sent after she made comments about the Black Country flag.
Mr Lammy and Ms Morgan attended court to give evidence against Hall when he entered his guilty pleas.
Speaking outside court Ms Morgan, Conservative MP for Loughborough, said: “MPs are of course subject to robust debate and scrutiny, which is what we should be.
“When things tip over into threats of violence or death, then I think a line has been crossed.”