San Francisco health officials declared a tent city that has been growing along a city street a health hazard and gave homeless people living on the sidewalk 72 hours to clear the area.

The Department of Public Health said notices declaring the area along Division Street a public nuisance and encouraging homeless people to move to city shelters would be posted Tuesday.

"Unfortunately, conditions where multiple tents are congregated have become unsafe," said Barbara A. Garcia, the department's director of health. "People are living without access to running water, bathrooms, trash disposal or safe heating or cooking facilities."

An inspection found that people in tents along Division Street between South Van Ness Avenue and 11th Street are living among garbage, human feces, hypodermic needles, urine and other insanitary conditions, the department said.

If people don't vacate by Friday, the department will recommend the San Francisco Department of Public Works and the San Francisco Police Department remove all encampments from the area, it said.

Mayor Ed Lee said at least two other encampments in the city would be cleared in the coming weeks.

"We're going to encourage people first to get out of those situations and persuade them. Persuasion usually means a backup from people who say you can't be here," Lee told the San Francisco Chronicle while touring the city's newest homeless shelter at Pier 80, which can house up to 150 people.

The health department said its homeless-outreach team has been urging campers to move to Pier 80 or other city shelters and will continue to do so through Friday.