Arrests of illegal immigrants at the U.S. border with Mexico during President Joe Biden’s first October in office were the highest ever recorded in the month, data released Monday show. Customs and Border Protection (CBP) made 164,303 arrests in October. That’s slightly higher than preliminary estimates and 55 percent higher than the previous high for the month. The bulk of those taken into custody, or two-thirds, were single adults. About a quarter were family units and the rest were minors who weren’t with a responsible adult. Agents saw a large jump in illegal immigrants trying again to enter the United States after being ejected before. About 30 percent of the arrests were of people agents had at least one encounter with in the previous 12 months. The numbers didn’t include illegal immigrants who evaded agents. That number was estimated to be around 50,000, according to internal data obtained by The …