(Adds details, quotes from governor, disaster site, church services)
By Jonathan Kaminsky and Bryan Cohen
DARRINGTON, Wash., March 30 (Reuters) - Churches offered prayers on Sunday for dozens of people dead and missing from last week's mudslide in Washington state, as well as words of solace for anguished families, many still waiting for official word on loved ones who vanished.
The formal death toll rose to 21 on Sunday, including the remains of 15 victims identified by medical examiners and six still awaiting positive identification, said Jason Biermann, program manager for the Snohomish County Emergency Management Department.
He said four additional sets of remains were found on Sunday that for reasons not explained to reporters were being left out of the official tally of dead.
Authorities have offered conflicting casualty figures in recent days, and the process of accounting for the number of dead has likely been complicated by the condition of some bodies that rescue workers have said are not always found intact.
Based on the four latest sets of remains reported found, and previous statements by county officials, the overall unofficial death toll could stand as high as 32.
In one hopeful development to the grim aftermath of the March 22 disaster, the roster of individuals still listed as missing and feared dead was lowered on Saturday to 30, down by two thirds from the figure that authorities had been reporting for several days.
That revision came after officials said they had accounted for the whereabouts of dozens of people who turned out to be safe and well.
Heavy showers and flooding this weekend hampered the efforts of teams searching for victims in the square mile (2.6 sq km) of muck and debris left when a rain-soaked hillside collapsed without warning above the north fork of the Stillaguamish River.
The torrent of mud released by the slide roared over both stream banks and state Highway 530, engulfing dozens of homes on the outskirts of the town of Oso in the foothills of the Cascade Mountains, about 55 miles (90 km) northeast of Seattle.
NO SIGNS OF LIFE
No one has been pulled alive from the rubble since the day the landslide hit, when at least eight people were injured but survived, and rescue teams have detected no signs of life in the ensuing eight days.
Authorities conceded that it may end up being impossible to account for everyone lost in the disaster. Ron Brown, a Snohomish County official, said the debris field might end up as the final resting place for some victims.
Governor Jay Inslee, who toured the disaster zone by helicopter and met recovery team members, said authorities had not yet abandoned all hope of finding a "miracle" survivor.
"The family members that I've spoken to, I think, have a very mature, real sense of wanting to have hope, and wanting to find that miracle ... and we're looking for that miracle right now," he said at an air field in the nearby town of Arlington.
"If we don't find that miracle, they're also looking for the knowledge of the fate of their loved ones."
Many living close to the disaster area gathered for services at the Glad Tidings Assembly of God church in Darrington, where Pastor Les Hagen urged them to remain strong.
"Stay in your routine," he said. "Keep putting one foot in front of the other. Because eventually all of this will be in the rear view mirror of your life and it will be a memory. It will be a horrible memory, but it will be a memory."
Scores of recovery workers continued to pick through the swampy, rubble-strewn mound of mud, as overcast but dry weather provided a respite from days of heavy rain.
In one muddy pond, about 20 workers in orange vests used shovels, pickaxes and rakes to sift through a spot that was until recently under too much water to search.
Among the search teams were troops from the Army and Air National Guard, including flight crew members of a medical evacuation unit that just returned from Afghanistan, said Major General Bret Daugherty, the state National Guard commander.
Some parts of the slide area, buried beneath as much as 80 feet (25 metres) of mud, twisted tree trunks and other debris, were still too dangerous to enter, said fire lieutenant Richard Burke, an on-site spokesman for the operation.
One key concern, he said, has been containing what has become, in effect, a large toxic waste site full of sewage, propane, household chemicals and other contaminants.
"We're worried about dysentery, we're worried about tetanus, we're worried about contamination," Burke said. "The last thing we want to do is take any of these contaminants out of here and take them into town, back to our families."
Recovery teams, aided by volunteers, have also been looking for personal effects, such as photographs and other keepsakes, that might have belonged to victims or survivors.
Such items will be cleaned and stored until they can be claimed by survivors or victims' families, disaster response spokeswoman Kris Rietmann told a news conference.
"A lot of people lost their homes. They lost friends and family, and so to be reunited with some of their physical belongings, if that's found out on the site, is a really important thing," Rietmann said.
At the Oso Community Chapel, where about 100 people filled the pews, a helicopter was heard overheard as prayers were said for the dead.
Pastor Gary Ray told the congregation: "We've been knocked down, but we won't be knocked out. I don't know how many days and minutes we have left, but I know we have this one here."
Funeral preparations were being made for those lost in the tragedy. At the Weller Funeral Home in Arlington, staff members who typically plan two to three funerals weekly said they were preparing for 12 this week. (Writing by Steve Gorman; Editing by Sandra Maler, Eric Walsh, Bernard Orr and Ron Popeski)