WASHINGTON — Threats against members of Congress continue to grow, Capitol Police Chief Steven Sund said Tuesday at his first appearance as head of the department before the House Administration Committee.

"We continue to see the threat assessment cases that we're opening continue to grow," Sund said. "For FY 2018, we had approximately 4,894 cases. So far for this year, we have 2,502 cases. So we're on par to probably break last year's."

Many first-year members of Congress have extremely high-profiles and face threats as a result, including four Democrats whom President Donald Trump has been recently disparaging on Twitter: Reps. Alexandria Ocasio-Cortez of New York, Ilhan Omar of Minnesota, Ayanna S. Pressley of Massachusetts and Rashida Tlaib of Michigan.

Following the president's tweeting that the four of them should go back to their "crime-infested" countries, House Homeland Security Chairman Bennie Thompson, D-Miss., sent a letter to Senate Sergeant-at-Arms Michael Stenger, who chairs the Capitol Police Board, to hold an emergency meeting to reexamine the board's approach to analyzing the risk environment, setting thresholds for enhanced security for certain targeted members and evaluating threat streams with law enforcement partners in member districts.

"On Sunday, July 14, 2019, President Trump used social media to directly attack four members of Congress," Thompson writes. "To date, Trump continues to use social media to vilify these four members."

Thompson also writes that "The President's rhetoric may insinuate more attacks on members of Congress."

The hearing comes as the House considers a resolution condemning the president's remarks, which have been widely criticized as racist — although notably not by House Republican leaders.

Meanwhile, at the committee hearing, Rep. Barry Loudermilk, R-Ga. — one of three Republican members of the committee who were on the baseball field when a gunman opened fire two years ago on their practice for the congressional baseball game — asked Sund about the level of threats directed at members.

"We firsthand witnessed not only the aggression toward us — the shots being fired — but also the bravery by the Capitol Police officers," Loudermilk said.

House Administration Committee ranking member Rep. Rodney Davis, R-Ill., another of those players, said without the bravery of the Capitol Police officers, "I wouldn't be standing here today."

Sund noted that a much lower percentage of threat cases investigated meet the threshold of being a credible threat, he did not provide an exact percentage breakdown.

House Sergeant-at-Arms Paul D. Irving, who also testified before the committee, said after the hearing that as members become more prominent in the media, his office provides enhanced support in their districts — by liaising with the district office's law enforcement coordinator and local law enforcement — when they're making appearances in public.

In the past, Irving said his office has always provided added law enforcement support for higher profile members and those more prone to threats when a member called and informed the office of threats.

"But we've been more proactive in reaching out to members to ensure that they all avail themselves of that service that we provide," Irving said. He added that for "at least the last several years" his office has been more proactive in that arena.