President Xi Jinping extended condolences on Saturday to Russian President Vladimir Putin over the terrorist attack that caused heavy casualties on Friday near Moscow.
In his message, Xi said he was shocked to learn that the serious terrorist attack had occurred at a concert hall in Russia's Moscow Oblast.
Xi, on behalf of the Chinese government and the Chinese people, expressed his deep condolences for the victims, and extended his sincere sympathy to the injured and the bereaved families.
He emphasized that China opposes all forms of terrorism, strongly condemns terrorist attacks, and firmly supports the Russian government's efforts to maintain national security and stability.
The attack by gunmen on Friday evening at the Crocus City Hall northwest of Moscow claimed the lives of at least 137 people, according to Russian authorities.
Anastasia Rodionova, a survivor of the attack, told China Daily on Saturday that the assailants were "gunning down everyone methodically in silence" inside the venue on Friday night.
"We went down to some kind of ground floor, some dark room, and I saw only 'exit' word shining in the darkness, and we just did not know whether to run or not. Who is there in the dark? What is there in the dark?" she said after she laid flowers at the Crocus City Hall on Saturday morning. The woman was quickly surrounded by international media as she tried to describe what happened on the night of terror.
"China is deeply shocked by the heavy casualties inflicted by the severe terrorist attack," the Chinese Foreign Ministry said in an online statement, expressing deep condolences for the victims and sincere sympathy to the injured and bereaved.
"China opposes all forms of terrorism, strongly condemns terrorist attacks, and firmly supports Russia in safeguarding its national security and stability," the statement added.
According to Russian state media Tass, four suspects were detained in the Bryansk region and taken to Moscow and were in the custody of Russia's Investigative Committee.
One suspect said he was promised a reward of 500,000 roubles ($5,400), according to a video posted on RT Editor-in-Chief Margarita Simonyan's Telegram channel on Saturday.
The detainee added that half the money had been transferred to his card, while he had been promised he would receive the other half later. He lost the card while trying to escape from law enforcement officers.
The terrorist group ISIS claimed responsibility for the deadly incident.
Leaders around the world expressed their condolences and condemned the terror attack.
United Nations Secretary-General Antonio Guterres condemned the attack, saying on Saturday at a news conference at El Arish International Airport in Egypt that ISIS is a significant global threat.
Putin linked the attack, which he called "barbaric", to Ukraine in a video statement released on Saturday, as he expressed deep condolences and declared Sunday a national day of mourning.
On Ukrainian national TV on Saturday, Andrii Yusov, spokesman for Ukraine's Defense Intelligence, firmly denied that his country had anything to do with the terror attack.
United States Secretary of State Antony Blinken denounced the attack as a "heinous crime" and said Washington condemns "terrorism in all its forms".
"We ... stand in solidarity with the people of Russia in grieving the loss of life from this horrific event," Blinken said in a statement on Saturday.
Earlier, the White House had called the attack "terrible" and offered condolences.
European Commission President Ursula von der Leyen said in a post on social media platform X on Saturday that she "strongly condemns" Friday's concert hall attack. "My thoughts are with the victims and their families during this tragic time," she said.
Turkish President Recep Tayyip Erdogan sent his condolences to the Russian government and denounced the attack as well. "Regardless of the origin of the suspects, terror cannot be accepted," he said.
Israeli President Isaac Herzog said he spoke with Russia's ambassador to Israel "to convey — on behalf of the Israeli people — my condolences to the families of the victims, to the Russian people and its leadership for the terrible loss of life", adding that he "wished a speedy recovery to all those injured".
Other European leaders, including those of France, Poland, the United Kingdom and Germany, also denounced the attack.