YEAR INVESTIGATION, DUBBED "OPERATION FROZEN TIMBER," HAS RESULTED IN THE ARRESTS OF MORE THAN 40 PEOPLE IN THE UNITED STATES AND SIX IN CANADA -- WITH SOME OF THE U.S. ARRESTS DATING BACK TO EARLY LAST YEAR. THE ANNOUNCEMENT CAME AS SOME AMERICAN POLITICIANS HAVE EXPRESSED CONCERN ABOUT SECURITY ON THE U.S.-CANADA BORDER IN THE WAKE OF THE RECENT ARRESTS OF 17 TERRORISM SUSPECTS IN TORONTO. OFFICIALS IN BELLINGHAM TOOK PAINS TO STRESS THE COOPERATION BETWEEN POLICE IN BOTH COUNTRIES. "MY EXPERIENCE TELLS ME THAT WHEN OUR COUNTIES ENJOY STRONG PARTNERSHIPS, LIKE THE ONE DEMONSTRATED HERE TODAY, WE ARE EFFECTIVE IN COMBATING ORGANIZED CRIME," SAID BUD MERCER, CHIEF SUPERINTENDENT OF THE ROYAL CANADIAN MOUNTED POLICE. THE BORDER IN THE PACIFIC NORTHWEST HAS LONG BEEN USED FOR SMUGGLING, LARGELY WITH MARIJUANA AND ILLEGAL IMMIGRANTS TRANSPORTED INTO THE UNITED STATES AND COCAINE AND GUNS SHIPPED INTO CANADA. OFFICIALS SAID THE TRANSPORTATION NETWORK TARGETED BY THIS INVESTIGATION WAS THE MOST SOPHISTICATED THEY HAD SEEN, USING AIRCRAFT -- PRIMARILY HELICOPTERS AND SMALL PLANES, SOME EQUIPPED TO LAND ON LAKES AND RIVERS. JAMES MCDEVITT, THE U.S. ATTORNEY FOR EASTERN WASHINGTON AND A PILOT, SAID THE RUGGED WILDERNESS TERRAIN MADE ENFORCEMENT DIFFICULT. "IT'S ABOUT AS REMOTE AS YOU'LL EVER FIND. WHO WANTS TO PAY FOR A RADAR SHED ON EVERY PEAK AND EVERY MOUNTAIN?" MCDEVITT SAID.