New federal data shared with The Washington Examiner show the number of migrants arrested at the US-Mexico border is the highest it has been since 2007.

About 851,000 people were apprehended and taken into custody by border patrol agents in fiscal year 2019, which ran from Oct. 1, 2018 to Sept. 30, 2019.

The number of migrants who claimed asylum once in custody has not been released by the federal government, and the figure does not include those turned away at ports of entry, nor does it include arrests at the US-Canada border or along the Pacific and Atlantic coasts.

More families than ever are being arrested at the US-Mexico border, with more than 450,000 people apprehended in fiscal 2019 having arrived with a family member, compared to fewer than 80,000 in 2015.

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The number of migrants being arrested at the US-Mexico border is the highest it has been since 2007, new federal data show. About 851,000 were apprehended and taken into custody by border patrol agents in fiscal year 2019, which ran from Oct. 1, 2018 to Sept. 30, 2019.

Federal data on migrant arrests was shared with The Washington Examiner. The US Customs and Border Protection agency has not released data on how many migrants were able to claim asylum after being taken into custody.

The number does not include those who approached designated ports of entry along the southern border. As of Aug. 31, not including the September figure (which has not yet been released), 263,000 migrants were denied entry at ports. Neither figure includes arrests or those denied entry at the US-Canada border or along the Pacific and Atlantic coasts.

Central American asylum seekers wait as U.S. Border Patrol agents take groups of them into custody on June 12, 2018 near McAllen, Texas. The families were then sent to a U.S. Customs and Border Protection (CBP) processing center for possible separation. Getty Images/John Moore

40,000 migrants were taken into custody in September after crossing the border into Texas, Arizona, New Mexico, and California, compared to 132,000 in August. None of the figures provided by CBP reflect the number of migrants who enter the US illegally without detection.

Of the migrants crossing the US-Mexico border in fiscal 2019, at least 250,000 were Guatemalan and another 250,000 were Honduran. Under President Donald Trump's Zero Tolerance policy, more migrant families have been arrested than ever.

Read more: A 3-year-old girl was asked to choose between her mom or dad as a border patrol agent tried to separate the family

More than 450,000 of the migrants arrested in fiscal 2019 arrived with a family member, compared to fewer than 80,000 of those arrested in 2015. The number of families arrested has only increased since the Border Patrol agency was created in 1924, with a sharp uptick under the Trump administration, in comparison to the total number of arrests, which has fluctuated.

Past data from US Border Patrol on the total number of apprehensions along the southern border show that, starting in 2008 — the first year of President Barack Obama's term, the number of total arrests began to decline sharply. During President George W. Bush's administration, the number frequently rose above 1 million.

Under Obama, arrests typically hovered under 500,000. Under the first two years of Trump's administration, before the Zero Tolerance policy was instituted in 2018, the numbers remained at about the level under Obama's administration. The most recent data indicate a sharp rise after Trump's 2018 policy — more than doubling the fiscal 2018 number — but there are still not as many arrests as there were under the Bush administration.