Federal law enforcement based on the U.S.-Mexico border are expected to encounter 1.1 million people trying to cross illegally by the end of the fiscal year Sept. 30, despite Mexico’s assistance stopping migrants on their journey north.

Senate Homeland Security and Governmental Affairs Chairman Ron Johnson forecast the 1.1 million figure during a committee hearing Tuesday based off the number of people arrested for illegally entering between border crossings and those who presented at ports of entry but were deemed ineligible for admittance.

As of June 30, U.S. Customs and Border Protection personnel had made contact with 905,926migrants, including 694,229 who entered the country without permission. The 694,229 figure nine months into fiscal 2019 was more than double the 310,000 who illegally crossed the southern border in all of fiscal 2017.

This year’s number has already surpassed the 683,178 encountered both at ports of entry and between ports in fiscal 2018.

Johnson, a Republican from Wisconsin, said the Border Patrol agents who work the spaces between border crossing points took 3,000 people into custody on an average day in June. The highest-ever day was recorded earlier this year when 4,652 people were arrested.

This fiscal year, nearly half a million children who traveled alone or people who arrived with a family member have been taken into custody.

“As of June, first nine months of this final year, 495,000 children and family units have come to this country. If June’s pace continues, we’ll be over 700,000,” Johnson said.

The hearing was focused on how to best care for the mass numbers of people who continue to arrive at the southwest border.

“Given this flow, no one should be surprised that Border Patrol stations are well beyond their capacity,” he said in a statement after the event. “Rather than point fingers at the brave men and women of DHS, who have done their best with the limited resources we have provided them, members of Congress should be acting on legislation to solve the underlying problems.”

Acting Homeland Security Secretary Kevin McAleenan said in March CBP facilities on the southwest border can comfortably hold 4,000 people, with 6,000 in custody putting the agency in crisis mode. In early June, the agency had 19,000 in custody.

The numbers dropped from 132,000 arrests for illegal entry in May to 94,000 in June. Johnson credited Mexico for deploying thousands of National Guard nationwide to intercept and deport people found to be illegally present in the country and traveling north to the U.S. But it is also true that historically, fewer people have been apprehended from spring into summer because of the heat.