REDDING, California - The deadly Northern California Carr Fire that has forced tens of thousands of people to flee their homes slowed down Sunday after days of explosive growth, giving officials hope even as they announced the discovery of a sixth fatality. Officials said there were more than 150 engines on the way from out of state to help.

Meanwhile, officials said a second firefighter died fighting a huge blaze to the south near Yosemite National Park. Brian Hughes, 33, was struck by a tree and killed while working as part of a crew removing brush and other fuel near the so-called Ferguson Fire's front lines, national parks officials said.

In Redding, officials stuck a hopeful tone for the first time in days.

"We're feeling a lot more optimistic today as we're starting to gain some ground rather than being in a defensive mode on this fire all the time," said Bret Gouvea, the California Department of Forestry and Fire Protection's incident commander on the blaze around Redding, a city about 230 miles north of San Francisco.

Gouvea spoke at a news conference with fire and law enforcement officials. Shasta County Sheriff Tom Bosenko said authorities found a sixth victim of the blaze at a home that was consumed by flames, though he declined to say where. The victim's identity was not released.

The sheriff's department is also investigating seven missing persons reports, Bosenko said. Redding police have an additional 11 reports of missing people, though many of them may simply not have checked in with friends or family, said Redding police Sgt. Todd Cogle.

The so-called Carr Fire that affected Redding -- a city of about 92,000 people -- was ignited by a vehicle problem Monday about 10 miles west of the city. On Thursday, it swept through the historic Gold Rush town of Shasta and nearby Keswick fueled by gusty winds and dry vegetation. It then jumped the Sacramento River and took out subdivisions on the western edge of Redding.

The latest tally Sunday night showed at least 874 homes destroyed and another 175 damaged. The fire had consumed 149 square miles and was threatening more than 5,000 structures. It was 17 percent contained.

After days of fortifying the areas around Redding, fire crews were increasingly confident that the city would escape further damage. The fire had not grown inside the city limits since Saturday, Gouvea said.

Some of the 38,000 people forced to evacuate said they were frustrated because they didn't know whether their homes were standing or were destroyed. Authorities had not reopened any evacuated neighborhoods where fires raged due to safety and ongoing investigations and urged people to be patient, saying they would soon let residents back.

The fatalities included two firefighters and a woman and her two great-grandchildren.  The sixth victim, who was not identified, did not evacuate despite receiving an evacuation warning, authorities say.

The Associated Press contributed to this report.