Infectious disease experts are warning authorities that deploying tear gas against people protesting across the country could help spread COVID-19.

More than 1,000 doctors, health experts, and others recently signed on an open letter that expresses support for protesters taking to the streets after George Floyd, a 46-year-old black man, died in police custody in Minneapolis last week. Also in that letter is a call for police to end the use of tear gas and respiratory irritants against protesters because they increase the risk of spreading the coronavirus.