The venue has served as an Emergency Intake Site (EIS) for unaccompanied migrant minors since April 22.
"We want to really thank the people of Long Beach who have really stepped up to make this a welcoming venue for these kids," Becerra said.
Alongside Long Beach city leaders, including Mayor Robert Garcia, Becerra met with those charged with operations at the EIS and with volunteers.
"All of the health care workers are in there, a full clinic and hospital setup. They're getting education four hours a day and they're playing. They look like any other kid in an environment they're comfortable in, but we also know that these centers have to be temporary," Garcia said.
There are ways for people to help directly at the site which is schedule to close in August.
RELATED: Reunification process reportedly underway for migrant children at Long Beach Convention Center
"Additional ways to help beyond the 70,000 books and toys that have been donated, is for folks to visit the longbeach.gov/migrantchildren page and there's information on how to volunteer. Right now we're doing a letter-writing campaign across the city to help write letters for the kids," Garcia said.
According to a spokesperson with HHS, 671 minors were housed at the Long Beach site as of Thursday, with 28 currently testing positive for COVID-19. That's about half of last week's total. The children at the EIS range in age from 5 to 17 years old.
Becerra said he was happy to see the minors in a welcoming environment.
"What I didn't see was grief. I didn't see shouting. I saw a lot of kids who were being kids," Becerra said.
According to HHS, by the end of Thursday, 102 children were set to be united with their families in the U.S. or sponsors.
MORE | Unaccompanied migrant children risk lifelong health effects, expert says