A red ribbon is displayed on the Paris City Hall in support of the fight against AIDS on World AIDS Day on Dec.1. Charles Platiau/Reuters
People gather to light candles during events for World Aids Day outside of the municipality at Eleftheria square in divided capital Nicosia, Cyprus on Dec. 1. Petros Karadjias/AP
People light candles for AIDS victims during an AIDS awareness event marking the World AIDS Day at Sergels Torg square in Stockholm, Sweden on Dec. 1. Janerik Henriksson/Scanpix/Reuters
A man holds a free condom taken from a signboard promoting HIV/AIDS awareness during World AIDS Day in Athens, Greece on Dec. 1. Yiorgos Karahalis/Reuters
Students form a red ribbon during an HIV/AIDS awareness rally on World AIDS Day at Marina beach in the southern Indian city of Chennai on Dec. 1. Babu/Reuters
An artist takes part in a HIV/AIDS awareness rally on World AIDS day in central Istanbul, Turkey on Dec. 1. Murad Sezer/Reuters
Activists form AIDS red ribbons during a HIV/AIDS awareness rally on World AIDS day in central Istanbul, Turkey on Dec. 1. Murad Sezer/Reuters
Health workers and students release balloons after they staged a march through the Philippine capital to spread awareness about AIDS during the World AIDS day in Manila on Dec. 1. Cheryl Ravelo/Reuters
A child touches a dress made of condoms during an HIV/AIDS awareness campaign on World AIDS day in Yantai, China on Dec. 1. Reuters
A member of the Population and Community Development Association wears a dress and holds an umbrella made with condoms during a march marking World AIDS Day in Bangkok, Thailand on Dec. 1. Chaiwat Subprasom/Reuters
The attack immediately raised the specter of terrorism, with Canada already on heightened alert because of a deadly hit-and-run earlier in the week against two Canadian soldiers by a man who police say was fired up with radical Muslim fervor.
ByJeremy Hainsworth and Rob Gillies, Associated Press
Adrian Wyld/The Canadian Press/AP
A gunman with a scarf over his face shot to death a Canadian soldier standing guard at the nation's war memorial Wednesday, then stormed Parliament in a hail of gunfire before he was killed by the usually ceremonial sergeant-at-arms, authorities and witnesses said.