Arizona's first death tied to the new coronavirus was reported Friday night as the reported statewide count of cases climbed to 76, with a "shelter-in-place" order announced on the Navajo reservation in northern Arizona.

A Maricopa County man in his 50s, who had underlying health conditions, died from COVID-19, the disease caused by the new coronavirus, the Arizona Department of Health Services and the Maricopa County Department of Public Health said in a joint statement.

The man was an employee of the Phoenix Aviation Department, according to a letter sent to employees from City Manager Ed Zuercher. In his letter, Zuercher said that the man worked in a remote office and had minimal public interaction within any of the terminals and related airport facilities.

“We express our deepest sympathy to the family and friends grieving their loved one during this difficult time,” Dr. Cara Christ, ADHS Director said in a prepared statement.

As of Friday, Maricopa County had 35 reported cases of COVID-19.

The new positives indicate the illness is spreading throughout the state. Ten of Arizona's 15 counties now have presumed positive or confirmed cases.

Yuma County and Cochise counties announced their first presumed positive cases Friday.

The Navajo Nation announced 11 cases late Thursday night, bringing the tally on the Navajo reservation to 14, and tribal president Jonathan Nez issued a "shelter-in-place" order for the community of Chilchinbeto in northern Arizona.

At least seven of the 11 new cases are from the community of Chilchinbeto, Navajo officials said. It's unclear whether the other four cases are in Arizona, New Mexico or Utah. The Navajo Nation includes land in all three states and did not specify in which state the affected patients live. (An earlier version of the story included those four cases in the Arizona count.)

Shelter-in-place means residents are required to remain in their homes to slow the spread of the virus. Nez said in a news release that the order may be applied to the entire reservation if reported cases become widespread.

The number of presumptive positive and confirmed cases in Arizona likely is much higher than the reported numbers because testing for the new coronavirus, which causes the COVID-19 disease, has been limited.

Maricopa County remains the county with the highest case count, at 34, data from the Arizona Department of Health Services shows.

Pinal County has 10 cases and Coconino County has eight, a county spokesman confirmed Friday. The state numbers show Pima County also has eight cases, up from seven on Thursday, and Yavapai, Graham, Santa Cruz, Cochise and Yuma counties each have one case.

The Yuma and Cochise cases were not included in the state data posted Friday morning. Navajo County appears to have at least 10 cases, based on tribal reports.

State data shows there are 101 tests with pending results. While the state numbers show 343 Arizonans have been tested, the numbers are likely higher because that tally does not include people tested by private labs.

SonoraQuest, LabCorp, the Translational Genomics Research institute and the Mayo Clinic are all now doing their own testing in Arizona.

The Arizona Department of Health Services recommends Arizonans cancel or postpone mass gatherings of 10 or more people.

Gov. Doug Ducey on Thursday announced he would limit restaurant service and close bars, theaters and gyms in counties with confirmed cases of COVID-19, stepping up Arizona's efforts to slow the spread of the new coronavirus.

The directive will take effect upon close of business Friday.

Ducey also:

Called on the National Guard to help grocery stores and food banks restock shelves to protect food supplies. Stores have faced "unprecedented demand," and food banks don't have enough volunteers.

Halted all elective surgeries "to free up medical resources and maintain the capacity for hospitals and providers to continue offering vital services."

Delayed expiration dates for Arizona drivers licenses, so that residents who are 65 or older don't need to wait in line at state offices to renew them.

Authorized restaurants to deliver alcoholic beverages with food, and allowed manufacturers, wholesalers and retailers to buy back unopened products from restaurants, bars and clubs.

The Johns Hopkins University COVID-19 resource center on Friday reported 255,305 cases worldwide, including 10,444 deaths. The U.S. Centers for Disease Control and Prevention on Friday reported the U.S. case count at 15,219, including 201 deaths.

Republic reporters Maria Polletta and Shondiin Silversmith contributed to this article.

Reach health care reporter Stephanie Innes at Stephanie.Innes@gannett.com or at 602-444-8369. Follow her on Twitter @stephanieinnes

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