A Leeds man has been arrested by police investigating reported threats against Normanton, Pontefract and Castleford MP Yvette Cooper.
The 59-year-old man was detained by West Yorkshire Police on Friday but has since been released on bail.
A Labour Party member, who did not wish to be named, said several officers had been present at a constituency party meeting that evening as a precaution.
Those attending the meeting in Airedale were asked to show their membership cards to officers as they arrived, he said.
It is not the first time Labour MP has had to report threats made against her to police.
In June 2016, shortly after the murder of Batley and Spen MP Jo Cox, Mrs Cooper received a threat against the lives of her children and grandchildren.
In a statement issued today, West Yorkshire Police said: "As a result of information received in relation to alleged threats against a serving MP, officers arrested a 59-year-old Leeds man in Castleford on Friday.
"He has been bailed pending further advice from the Crown Prosecution Service."
Mrs Cooper has been approached for comment.