More than 700,000 foreign travelers who traveled to the United States legally in 2016 overstayed their visas and remained in the country, according to the Department of Homeland Security.

"This report shows that we have a problem with visa overstays in the United States," a senior administration official said in a briefing with reporters on Monday.

Roughly 740,000 people remained in the country illegally at the end of 2016, according to the report — though some of them were short-term overstays. A majority of them were long-term overstays, though: Nearly 630,000 were still in the U.S. at year's end, for a rate of 1.25 percent.

DHS said Monday that it is working to review the records of people violating their visas or visa waiver program, and is working with Immigration and Customs Enforcement to better deport those in the country illegally.

"Identifying overstays is important for national security, public safety, immigration enforcement, and processing applications for immigration benefits," the report says.

According to DHS, individuals with student visas violated their stays the most, with an overstay rate of 2.8 percent.

DHS made it clear that the data does not include border crossings.

The Office of Inspector General at DHS revealed in May that the agency catches less than 1 percent of people whose visas have expired.