Recent U.S. immigration policies reduced Venezuelan migration to the U.S.-Mexico border in October, but overall migrant apprehensions remained high, fueled by the arrival of tens of thousands of Cubans and Nicaraguans, according to federal statistics released late Monday.

According to Customs and Border Protection data, US immigration officials encountered migrants 230,678 times along the southern border last month, a 1.9% increase from September. Approximately 19% of those encounters involved migrants who had previously been processed by US border agents.

The Border Patrol apprehended 204,273 illegal immigrants, a slight decrease from September, while the Office of Field Operations, another CBP agency, processed 26,405 migrants at official ports of entry, where the Biden administration has been admitting certain asylum-seekers.

Venezuelan migrants were processed 22,044 times in October, a 35% decrease from the previous month’s record high of 33,804. The drop comes after the United States began deporting Venezuelans to Mexico on October 12 under a public health order known as Title 42. The Biden administration also launched a program to allow up to 24,000 Venezuelans to enter the United States legally if they have financial sponsors in the United States.

The arrival of 28,848 Cubans and 20,917 Nicaraguans, a monthly record for the latter nationality, offset the drop in Venezuelan migration. Because Cuba and Nicaragua do not accept regular US expulsion flights, Mexico has generally refused to allow the US to expel Cubans or Nicaraguans to its territory, prompting US officials to allow the majority of them to seek asylum within the country.

After Chris Magnus resigned as CBP commissioner last weekend, Troy Miller said migration from Cuba and Nicaragua remained at a “historic high” due to political and economic turmoil in both countries, which are ruled by repressive regimes.

“This reflects the hemispheric challenge of displaced populations fleeing authoritarianism, corruption, violence, and poverty,” Miller said in a statement.

According to CBP calculations, the number of unique migrants from Cuba, Nicaragua, and Venezuela in October surpassed the number of migrants from Mexico, Guatemala, Honduras, and El Salvador taken into U.S. border custody, continuing an unprecedented demographic shift to which the United States has struggled to respond.

In October, the United States deported over 78,000 migrants, including 5,855 Venezuelans. Those expelled under Title 42 are barred from seeking asylum, which is something that migrants can do if they are on US soil, regardless of whether they entered the country illegally.

Migrants who are not deported under Title 42 are subject to U.S. immigration law. In most cases, this means they are transferred by Border Patrol to another agency, released with instructions to appear before a judge or an immigration office, or processed through an expedited removal process.

While the United States struggles to deport many migrants who are not from Mexico or Central America for diplomatic and logistical reasons, the Biden administration has exempted several groups from Title 42, including unaccompanied minors and vulnerable asylum seekers.

According to data released on Monday, the migration wave to the United States-Mexico border during President Biden’s administration has continued to defy pre-pandemic seasonal patterns, in which migrant arrivals peaked in the spring and declined in the hot summer months.

The statistics also suggest that migrant encounters along the southern border will continue to resemble, or perhaps surpass, the record levels reported in fiscal year 2022, when U.S. immigration officials encountered migrants nearly 2.4 million times, an all-time high.