WATCH: Secret Service holds news briefing on the Trump assassination attempt

The U.S. Secret Service held a news briefing on Friday on its response to the attempted assassination of former President Donald Trump.

Watch the event in the player above.

The briefing comes as more Americans express doubt about the Secret Service’s ability to keep presidential candidates safe, a new poll from the Associated Press-NORC Center for Public Affairs Research finds.

Only around 3 in 10 Americans are extremely or very confident that the Secret Service can keep the presidential candidates safe from violence before the election, according to the poll. The survey also found that about 7 in 10 Americans think the Secret Service bears at least a moderate amount of responsibility for the assassination attempt.

The law enforcement agency tasked with protecting presidents for more than a century is under intense scrutiny after a gunman got within 150 yards of Trump and fired several bullets from an AR-style rifle. Trump was injured in one ear but was millimeters away from being killed.

The poll was conducted after the resignation of director Kimberly Cheatle, who faced intense questioning at a congressional hearing that was broadcast live last week and in which she gave evasive answers. The new acting director Ronald Rowe said earlier this week that he was “ashamed” after the July 13 attack in Butler, Pennsylvania, saying he considered it indefensible that the roof used by the gunman was not secured.