Thousands of miners protesting a biting economic crisis marked by fuel shortages bring Bolivia's administrative capital La Paz to a standstill. The helmeted miners march through the city and block avenues leading to the center. Bolivia, a producer of silver, zinc, lithium and tin, has for months been crippled by a shortage of dollars which has left the country teetering on the brink of economic collapse. The lack of hard currency has led to shortages of imported fuel, causing prices of goods to soar and agricultural and mining output to plummet. IMAGES AND SOUNDBITES