FBI Director Christopher Wray intends to inform the House of Representatives on Thursday of the office's concern about the possibility of an organized attack on the United States similar to the one that killed dozens of people in a Russian banquet hall last month.

Ray will tell US lawmakers during a budget hearing that “based on his professional experience in law enforcement, it was difficult for him to consider the possibility of so many threats to public safety and national security simultaneous...but that is the situation as I sit among you today.”

He will say during his testimony that the FBI is more deeply concerned about a more coordinated attack after the concert massacre in Russia.

He will also inform them that concern is growing about "the possibility of a coordinated attack here on our territory, similar to the ISIS-K attack that we witnessed in a concert hall in Russia a few weeks ago."

Wray also intends to pressure lawmakers to renew the “Surveillance America” program, which is expected to expire this month, and will describe it as “a vital tool against the United States’ adversaries.”

A simple amendment to the program was rejected in the Council on Wednesday due to concerns expressed by members of both parties that it did not include sufficient guarantees to curb the government’s surveillance powers. Wray plans to tell lawmakers that the program is "essential to securing our country, and we are in a difficult time."

The attack on a banquet hall on the outskirts of Moscow on March 22 led to the deaths of at least 144 people, making it the deadliest attack Russia has witnessed in 20 years.

A group affiliated with the Islamic State claimed responsibility for the attack, but Russian President Vladimir Putin blamed Ukraine without revealing evidence.

American officials are concerned about the possibility of launching an attack, whether individually or by a small group, due to the Israeli war on the Gaza Strip.

Russia reportedly questioned US assertions that ISIS was responsible for the armed attack on a concert hall outside Moscow.

In an article in the Russian Komsomolskaya Pravda newspaper, Russian Foreign Ministry spokeswoman Maria Zakharova said: “A question for the White House: Are you sure it is ISIS? Can you think about it again?”

She added that the United States is using the "scarecrow" of ISIS to cover up its actions in Kiev, and reminded readers that Washington supported the "mujahideen" who fought against Soviet forces in Afghanistan during the 1980s.