FIRST ON FOX: Republicans on the House Homeland Security Committee are marking the completion of 100 days in charge of the high-profile committee, during which they say they have made a running start on "well overdue" oversight of the Department of Homeland Security (DHS) on issues such as the border crisis, counterterrorism and the threat from China.

"Last Congress, Democrats largely ignored many significant homeland security issues that impact Americans across the country," Chairman Mark Green said in a statement to Fox News Digital.

"Over the first 100 days of a Republican Majority, the House Committee on Homeland Security carried out well overdue oversight actions to hold the Biden administration accountable for two years’ worth of damage to our homeland security," he said.

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March 15, 2023: Rep. Mark Green questions Border Patrol Chief Raul Ortiz. (Screenshot)

Republicans had eyed issues like the ongoing migrant crisis as some of their top priorities ahead of taking control of the House in January. The crisis has exploded under the Biden administration with over 1.7 million migrant encounters in FY 2021 and more than 2.3 million in FY 2022.

While the administration has outlined a hemisphere-wide crisis that it says it is dealing with by opening legal asylum pathways that were decimated under the prior administration, while highlighting a decrease in numbers in the last few months, Republicans have pointed to the policies implemented by the Biden administration and the leadership of DHS Secretary Alejandro Mayorkas – arguing that the policies have fueled the historic surge.

Having spent much of 2022 promising to take the administration to task on the crisis, Republicans have so far made the crisis a key area of focus in 2023. Republicans say that under their leadership, the committee has conducted over 340 oversight activities related to Homeland Security issues -- including 230 briefings and meetings, 23 oversight and document requests letters, over a dozen site visits and seven hearings.

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Ortiz Border Patrol

March 15, 2023: Border Patrol Chief Raul Ortiz testifies at a Homeland Security hearing. (Screenshot)

Additionally, the committee has launched 19 investigations into issues such as border wall construction contracts, DHS' approach to tackling alleged misinformation and disinformation, the Chinese threat to homeland security, and the use of alternatives to detention (ATD) and parole to allow migrants into the U.S.

Perhaps the most striking example of the oversight on the migrant crisis was a bombshell hearing in March, during which Border Patrol Chief Raul Ortiz told lawmakers that the agency did not have operational control of the border, and indicated that a number of sectors were at crisis levels of migrant traffic. He also stood by agents who were falsely accused of whipping migrants in 2021.

Lawmakers also made 8 site visits related to the crisis and hearings that included a visit to Pharr, Texas with Ortiz. The visits are expected to help inform lawmakers in creating legislation to solve the crisis.

Additionally, amid growing concerns about the threat from the Chinese Communist Party, the committee had conducted a dozen oversight actions including hearings, briefings and two bills to protect academic institutions and national security intelligence from Chinese influence.

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On other national security threats, Republicans identify over 80 moves to strengthen cyber defenses, including meetings with the executive branch and stakeholders including those in the private sector, and over a dozen briefings and site visits related to counterterrorism.

The work of the high-profile committee is likely only to increase in future months, with growing tensions between China and Taiwan and the looming end to the Title 42 public health order on May 11 -- which officials have feared with lead to a fresh spike in migrants at the southern border over the summer months.