Seattle, April 19 (RHC)-- The death toll of the massive mudslide that covered the town of Oso in the U.S. state of Washington has reached 39, according to officials on Thursday.

Four names are left on the list of the missing victims while all the 39 victims have been identified, the Snohomish County medical examiner's office reported.
One body was found on Monday and two on Tuesday in the south-east corner of the debris field, where the U.S. Army Corps of Engineers has erected a berm in the past week.  Koshare Eagle, a spokeswoman for the incident management team, said the berm is 914m long and made of nearly 20,000 tons of rock, gravel and dirt.  The berm allows standing water to be pumped back into the North Fork of the Stillaguamish River for searchers to enter the area.

U.S. Transportation Department engineers are trying to clear a one-mile highway that is covered with mud and trees up to 8 meters deep.  Officials say it may take one to three months to completely clear the highway.

The mudslide destroyed a residential neighborhood nearly 90 km north of Seattle.  Immediately after the disaster, authorities estimated that more than 160 people had not been accounted for.  The number has shrunk and the likely death toll now appears to be around 50.  Authorities say some bodies will probably remain buried.

U.S. President Barack Obama is expected to visit the site next Tuesday to survey the damage and meet the victims and emergency responders.  According to UPI, the landslide is the third deadliest natural disaster in Washington history.  The 1980 Mount St. Helens eruption killed 57 and a 1910 avalanche in Stevens Pass buried two trains, killing 96 passengers and rail employees