NEW YORK, June 11 -- Counter-terrorism efforts in recent years are characterized by a shift to prevention although interdiction and response remain their main thrust, experts have said.

"The best way to combat terrorism is to collect, analyze and share intelligence, especially about suspected terrorist groups and individuals," former FBI special agent Richard Marquise told Xinhua in a recent interview.

After Sept. 11 terrorist attack, the U.S. government has shifted its focus to preventive measures in its counter-terrorism efforts, and created a country-wide program to monitor "suspicious activities," said Marquise, who had led the U.S. Task Force investigating the Lockerbie bombing which included the FBI, Department of Justice and the Central Intelligence Agency.

A bomb, believed to be planted by Libyan intelligence officers, blew up the New York-bound Pan Am flight 103 flew over the Scottish town of Lockerbie on Dec. 21, 1988, killing 270 people.

This Suspicious Activity Reporting (SAR) program, a joint effort of the FBI and the Department of Homeland Security, asks 800,000 state, local and tribal police officers to report bits of intelligence they collect about "suspicious activities."

The state fusion centers will in turn analyze the information and report information to Joint Terrorism Task Forces (JTTF) which are located all over the United States. As a result, dozens of possible terrorist attacks have been prevented and many terrorists have been arrested and convicted.

Marquise said it has been well recognized that every terrorist plot is normally a long process which requires surveillance, information collection, material acquisition, training and preparation before the attack.

"If these indicators can be recognized by well trained law enforcement and intelligence agencies who believe their job to protect their country outweighs their own organizational goals, that country will be successful," he said.

Most important of all is the cooperation of the community, Marquise said, noting he has trained police officers all over the world and often tells them the most important part of their job is to develop community trust.

"Community trust in law enforcement is essential," he said.

"Only by demonstrating that the officers are professional and not corrupt will community members feel confident that if they report possible criminal or terrorist behaviors that information will be taken seriously and investigated properly."

Peter Romaniuk, senior fellow with the New York office of the Global Center on Cooperative Security, highlighted the need for the governments around the globe to reduce the appeal of extremism by identifying which groups or which communities are vulnerable to extremism and addressing grievances in a way that stops young people in particular from wanting to become extremists.