WASHINGTON (Reuters) - A package addressed to US Homeland Security Secretary Janet Napolitano ignited on Friday at a postal facility in Washington, DC but was quickly extinguished and no one was injured, authorities said. A postal worker was tossing mail into a bin when the package was discovered 'popping, smoking and with a brief flash of fire, Cathy Lanier, chief of the Washington Metropolitan Police Department, said during a news conference. The package was addressed to Napolitano and was believed to be similar to others found in two incidents involving packages delivered to Maryland state offices on Thursday, a Department of Homeland Security official said.