One of the leaders of Sussex Friends of Israel leader has had his Twitter account suspended after bombarding the director of Yachad with "threatening" tweets over IsrAction Day.
Simon Cobbs told Hannah Weisfeld that her group was anti-Israel and pro-boycott.
Ms Weisfeld said: "Since IsrAction Day was announced I have been harassed on Twitter demanding to know whether Yachad is participating. It culminated with Simon Cobbs threatening if we don't reply he would 'slaughter me'."
The Tweet read: "COME ON @YachadUK & @hannahweisfeld DO YOU SUPPORT #ISRACTIONDAY? If I don't get a simple yes or no, I'm going to slaughter you tomorrow!"
Ms Weisfeld reported the post to Twitter and Mr Cobbs' account was suspended.
Mr Cobbs told the JC: "I wholeheartedly apologise to Ms Weisfeld for the tweet. I used a term - slaughter - that many sporting fans would recognise, meaning to be unceremoniously defeated. I never imagined that it would be interpreted in a literal sense.
"I will admit that I am angry that Yachad will not join us in supporting IsrAction."