PHOENIX — Demand for tests has been growing especially in underserved communities of color in Arizona, which the COVID Tracking Project says has now has a 7-day average positive test rate above 20 percent.

On Saturday, dozens of people waited for as long as 13 hours in triple-digit temperatures outside a sports complex for free drive-up COVID-19 testing in the sprawling west Phoenix community of Maryvale, a predominantly working class neighborhood of Hispanic families.

Tomás Leon, senior vice president for Equity Healthcare, said staff had to turn people away as night approached, after nearly 1,000 tests were administered by the private firm that focuses on equitable health care.

“I’ve never heard of that many people showing up to any of the testing events,” said Leon, who attended the event. “Usually it’s about 100 people.”

Equity Health plans another free testing event for people without insurance at the same Maryvale site next Saturday, Leon said.

“We were really overwhelmed by the response to our grassroots effort to get out the word,” said Leon.

He said a testing event that Equity Health held May 16 at an African American church in downtown Phoenix drew more than 300 people.