Protests have erupted in San Diego after a church bulletin suggested that the devil is working through Democrat presidential nominee Hillary Clinton.

According to the San Diego Union-Tribune, the suggestion came in an article in the weekly bulletin for the Immaculate Conception Catholic Church on October 30.

It prompted demonstrations at the church this weekend and calls for the church's priest, Father Richard Perozich, to be removed from office.

One protestor told NBC 7: "I don't think any leader should be telling anyone how to vote. It really comes down to the individual and their conscience how they want to vote."

Another demonstrator, Father Dermot Rogers - a pastor from a church not affiliated with the Catholic diocese - said voters should "not be influenced by religious organisations or by churches".

"This is a violation of the great principle of separation of church and state. A pillar upon which our democracy is built and this is an egregious, egregious violation of that principle," he said.

Perozich, meanwhile, defended the article. "The fact that people from other Catholic parishes, other faith communities, or other non-religious wish to comment would be an exercise of their free speech, the very exercise they are trying to deny me because it does not fit their agenda," he told NBC 7.

"I will continue to guide my flock to live out their faith in Jesus."

The article follows a previous controversy on October 16, when a flier was inserted into the church's bulletin warning that parishioners who voted Democrat risked "descending into Hell".

"It is a mortal sin to vote Democrat... immediately after death the souls of those who die in a state of mortal sin descend into hell," it said.

Perozich said this flier was inserted by a group not affiliated with the church, and he did not agree with their claims.

Bishop of San Diego, Robert McElroy, said in a statement: "It is contrary to Catholic teaching to state that voting for a Democrat or Republican automatically condemns the voter to hell".

He urged Catholics to consult a statement written by the US Conference of Catholic Bishops on "the substantive implications of Catholic faith for the current election".

"Pray about the vote that you are going to make, and then in conscience select the candidates whom you are going to vote for in this very difficult year," he said.