Faced with a surge in drug-related killings in recent days, President Felipe Calderon on Monday offered a spirited defense of his government's antidrug offensive. On Thursday night and Friday morning, attacks between rival drug trafficking organizations left 85 people dead in states across Mexico, according to newspaper tallies, making it the bloodiest 24-hour period in Calderon's three-year-old presidency. Calderon responded with his most extensive defenseof his administration's drug war, a 5,000-word missive published on the presidential Web site and in local newspapers that shifted some blame for violence to previous administrations and to the United States and insisted that backing down was not an option. 'If we remain with our arms crossed, we will remain in the hands of organized crime, we will always live in fear, our children will not have a future, violence will increase and we'll lose our freedom,' Calderon wrote. On Monday, as television and radio commentators analyzed the president's statement, authorities announced another bad day, with 10 federal police officers killed and more than a dozen others wounded in a clash with traffickers in Zitacuaro, a town in the central state of Michoacan. The gunmen, some of whom died as well, used buses to close off major highways and obstruct reinforcements by the authorities, an increasingly common tactic employed by Mexico's drug cartels. In another episode on Monday, 28 inmates were killed and 3 guards were wounded in an uprising led by detained traffickers in a prison in Mazatlan, in the Pacific state of Sinaloa, authorities said. The president, elected in 2006 to a six-year term, also condemned the huge demand for drugs and the easy availability of guns in the United States. 'It is as though we have a neighbor next door who is the biggest addict in the world, with the added fact that everyone wants to sell drugs through our house,' Calderon said. 