PHOENIX (3TV/CBS 5) - The number of "dead body" calls Phoenix Police are responding to has been rising sharply since February, and Phoenix firefighters are starting to ask more questions when they arrive on the scene, about whether COVID-19 could be the cause.

But according to interviews and email exchanges with county state officials, firefighters, police officers, and public health experts, when police and firefighters respond to a death in a home or other non-medical location, there is no uniform procedure to identify cases where COVID-19 could have been a cause of death and get the bodies tested before they are cremated or buried.

The result, according to public health officials who spoke to CBS 5 Investigates, is that the actual death toll from COVID-19 may be much higher than the state's tally.

Beginning in mid-March, the Maricopa County Office of the Medical Examiner began asking additional questions when responding to deaths when the decedent died of apparent natural causes.

"If a death meets criteria based on the completed screening checklist, the body will be released to a funeral home where an MDI [Medicolegal Death Investigator] will respond to collect a Nasopharyngeal Swab for COVID testing," wrote Fields Moseley, who is the Maricopa County communications director.

Moseley stated that nasal swabs have been collected on seven occasions so far.

Phoenix firefighter-paramedics began asking follow-up questions in the past week that are meant to help determine whether COVID-19 played a role in deaths that would otherwise appear to be natural, according to one Phoenix Fire official.

But officials from police and fire departments in other parts of the Valley say they are not following any standard protocol for determining whether a death at home or somewhere else outside a medical facility was COVID-related.

In other counties, officials say there are no processes in place to test people who died. Part of the problem is that many people infected with COVID-19 are asymptomatic. And the virus can cause heart attacks, which are not automatically connected to the outbreak.

But deaths outside of medical settings appear to be rising. According to an analysis of Phoenix Police calls for service, the number of "dead body" calls has risen from 120 in February to 155 in March. April is on track to reach 190.The data do not show the causes of death in those cases.