South Korean police have stepped up security at the world university games in Taegu after a tip-off that Islamic radicals could carry out a chemical weapons attack on the venues.
More than 7,000 athletes and officials from over 170 countries are set to participate in Taegu, including 137 from the United States and 99 from Britain.
Police had heightened surveillance and stepped up checks on vehicles around venues in response to the alert, the South Korean Environment Ministry said.
The ministry said an anti-terrorist squad, including a special chemical weapons team, would be in place to respond to any attack during the games but that the extra measures were just a precaution.
Police have restricted the access of vehicles carrying dangerous materials within five kilometres of the venues.
Security has also been heightened around the North Korean team's accommodation.
This week, a man (31) was detained after police found weapons in the back of his car as he tried to park at the official games hotel in Taegu.