Evangelical Christians have been attacked as they left the fourth night of the Republican National Convention, where President Donald Trump formally accepted the party's nomination for a second term in the White House.

After more than 100 prominent evangelical leaders attended the event, many attendees were threatened with violence by protesters outside, in what one pastor has described as a "Democrat-endorsed" incident.

Among the Christian leaders who attended Trump's speech were Pastors Robert Jeffress, Ed Young, Jack Graham, Jentezen Franklin, Bishop Harry Jackson, and radio host Eric Metaxas.

Pastor Johnnie Moore, who was one of the leaders attacked outside, has reported, "Violent provocateurs waited for us (and others) outside the White House gates in the city's jurisdiction, at nearly midnight.

"Rather than succeeding at intimidating us with their vicious threats of violence, expletives, blasphemous slogans, hatred and intolerance they simply proved the very points the president made in his speech."

He added, "No doubt, D.C.'s Democrat mayor slept peacefully in her bed while these threats, attacks and insults were not even reserved for the elderly, disabled or young.

"I saw it with my own eyes and heard it with my own ears. What's awful is that the very thing this does is take away the voice of peaceful protestors, whom we want to hear."

Moore said what took place was "Democrat-endorsed and Democrat-enabled anarchy."

At the fourth night of the Republican National Convention, Trump made a 70 minute acceptance speech, during which he addressed abortion, one of the hot button issues for Christians.

Trump said, "Joe Biden claims he has empathy for the vulnerable — yet the party he leads supports the extreme late-term abortion of defenseless babies right up until the moment of birth.

"Democrat leaders talk about moral decency, but they have no problem with stopping a baby's beating heart in the ninth month of pregnancy."

He added, "Tonight, we proudly declare that all children, born and unborn, have a God-given right to life."

The president is hoping for strong support from U.S. Christians. During the 2016 election he received the support of 80 percent of white evangelical voters.