China and Afghanistan expressed "strong rejection" of the "three forces" of terrorism, extremism, separatism and organized crime in a joint declaration released?in Beijing?on Friday after talks between Chinese President Hu Jintao and Afghanistan's President Hamid Karzai.

The two sides agree to intensify exchanges and cooperation in security by way of jointly combating such transnational threats as terrorism, illegal immigration, illegal arms and drug trafficking, and enhancing intelligence exchanges and border management, said the declaration.

The two sides will also strengthen cooperation in prevention of infectious diseases, disaster prevention and reduction, and other non-traditional security areas, it said.

The Chinese side firmly supports Afghanistan's efforts in combating terrorism and drug trafficking and safeguarding national stability, the declaration added, calling on the international community to support this cause.

The Afghan side reiterated its continued and firm support for China in combating the "three forces" of terrorism, extremism and separatism. It will take tangible measures to enhance the security of Chinese institutions and people in Afghanistan, according to the declaration.

At the invitation of President Hu, President Karzai participated in a Shanghai Cooperation Organization summit and visited China from June 5 to 8.