Army green cots are up inside the San Antonio Freeman Expo Center Emergency Intake Site (EIS). 

500 migrant children are expected to spend their first night at the center Monday night. 

Officials said the center will provide shelter for 13 to 17 year-old-males, providing up to 2,100 beds inside and 300 medical beds outside.  

The children will receive clothing, toiletries, food and a medical screening.