Several Labour MPs who backed military action have spoken of the abuse they received, including threats of de-selection. The protest outside the constituency office of Ms Creasy in Walthamstow was on Tuesday night before the Commons vote next day.
Another demonstration is planned for Sunday to coincide with a public meeting which the MP called to explain her decision to back action.
Mr Watson said today: “I’ve seen those TV images of what went on in Stella Creasy’s constituency, the intimidation her staff must have felt.
“I can only say that if there were Labour members on that demonstration, intimidating staff members of an MP like that, then I think they should be removed from the party.”
The Metropolitan Police has increased patrols near Mr Coyle’s home and was considering stationing someone outside his office today because of further threats to disrupt his weekly surgery.
The MP said he welcomed an email sent from Mr Corbyn to party members calling for good behaviour.
But he went on: “Where I don’t think enough is being done is that bit that goes beyond party members.
“Momentum in particular pretends to act in the name of Jeremy Corbyn and it is not being told to back off or calm down.”
He added: “There isn’t enough being done to tackle some of the nastiness and the vitriol from Momentum.”
Mr Coyle said he had received an email of apology from one man who had sent him a tweet containing knife emojis. It is not clear whether the man is connected to Momentum.
In his note saying sorry, the man wrote: “I sincerely apologise. It was more of a show of anger than a threat. Frustration at the decision made re- garding Syria. I shouldn’t have sent that tweet in the first place.”
Momentum said it “strongly disapproves of anyone who engages in abusive behaviour”.
It added in a statement: “Momentum is not a threat to MPs who voted for bombing.
"We have made clear we will not campaign for any MP’s de-selection and will not permit any local Momentum groups to do so.”