Precarious climate

"So in this precarious security climate, the most important thing is to stabilize the situation and prevent more terrorist incidents and casualties."

Last year the Investigative Committee underscored the prevention of extremist and terrorist crimes as one of its top priorities, Wan said. Putin presided over two pivotal meetings of the Standing Committee of the Security Council.

One such gathering, in February last year, was dedicated to counterterrorism measures, and the other, in October, concentrated on combating the illegal trafficking of weapons and ammunition in Russia.

Experts also said the world must work together to tackle increasing security threats.

After Friday's attack, several countries condemned terrorism and called for a global push to counter it.

The Ministry of Foreign Affairs of Saudi Arabia condemned what it called "the armed terrorist attack", stressing the "importance of fighting and combating all forms of extremism and terrorism".

Qatar reiterated its "firm position on rejecting violence and terrorism, regardless of motives and reasons".

Malaysia's Ministry of Foreign Affairs reaffirmed its stance in "rejecting terrorism and violent extremism in all forms and manifestations", and "continues to underscore the urgent need for a concerted international effort to eliminate the scourge of terrorism in a comprehensive and effective manner".

The United Nations Security Council offered its condolences and urged all states "to cooperate actively" with the Russian government and other authorities to hold perpetrators and backers of "these reprehensible acts of terrorism accountable and bring them to justice".

Zhu Yongbiao, executive director of the Research Center for the Belt and Road at Lanzhou University in Gansu province, said: "Terrorism presents a common threat to all members of the international community, and no single country can effectively address this global challenge alone. Collaboration among all nations is the sole feasible approach.

"Faced with constraints on deepening international cooperation, Russia may seek to advance its counterterrorism cooperation agenda through engagements with pertinent countries and international bodies because it is going to host the BRICS summit and other international events this year."

Jan Yumul in Hong Kong and agencies contributed to this story.