Protesters chanted "Tory scum" and tried to block Conservative battle buses as Theresa May was driven out of Halifax after the launch of the manifesto.
Around 150 demonstrators gathered outside the Dean Clough centre with some trying to stand in front of the two coaches containing the PM and the Cabinet.
The front bus stopped a couple of times and police gently moved aside the group, which included a middle aged woman and her dog.
Mrs May was in the second vehicle, which swept past the screaming protesters without incident. Around two dozen police guarded the area.