A storm of condemnation from the international community on the knife attack in southwest China's Kunming train station on Saturday, which killed 29 people, continued to grow as more countries extended condolences and voiced support of anti-terrorist fight.

In contrast to the previous reports of several U.S. media outlets who had placed terrorists under quotation marks in their coverage, the United States on Monday called the attack "an act of terrorism" and extended its condolences for the loss of life.

"Based on the information reported by the Chinese media, this appears to be an act of terrorism targeting random members of the public, so we are calling this an act of terrorism," State Department Spokeswoman Jen Psaki told a press briefing.

"We acknowledge that China has characterized the incident as a terror act," Psaki said.

The United States extends its condolences for the loss of life, said Psaki, adding that the country opposes terrorism "in all of its forms."

"We deplore violence intentionally directed at innocent civilians in any case regardless of the cause," Psaki said.

The Turkish Foreign Ministry also issued a statement on Monday, sharply condemning Saturday's terrorist attack at the Kunming train station and extended sympathy and condolences to the victims and their families, hoping that the wounded will recover as soon as possible.

Turkey said it has always stressed that terrorist attacks targeting innocent civilians is unacceptable, adding that those who are responsible for the attacks must be brought to justice.

South Korean Deputy Foreign Minister Lee Kyung-soo on Monday denounced the terror attack, during a meeting with Chinese ambassador Qiu Guohong.

"South Korea sent its deep condolences and sympathies to innocent victims and those injured or who have lost their families in the attack," said Lee.

On the same day, Iran slammed the terrorist attack that killed at least 29 people, Press TV reported quoting Iranian Foreign Ministry spokeswoman Marzieh Afkham as saying.

"The Islamic Republic of Iran, as a victim of terrorism, expresses its opposition to terrorist acts in any forms," Afkham said, expressing sympathy with the families of the victims of the incident.

Singaporean Ministry of Foreign Affairs spokesman, in response to media queries on the attacks at the Kunming train station, strongly condemned the violent attacks and expressed deepest condolences to the victims and their families and wish those injured a quick recovery.

"Such attacks on innocent civilians cannot be pardoned or justified under any circumstances," said the spokesman.

Cambodia on Monday condemned the chilling attack and backed China's measures to crackdown on all forms of terrorist activities, said a statement released by the country's Ministry of Foreign Affairs.

In a statement issued on Monday, the Hungarian Foreign Ministry said it condemned all forms of terrorism and deemed all violent acts targeting innocent civilians unacceptable.

Indian External Affairs Ministry also issued a statement on Monday, condemning the March 1 terror attack in Kunming.

"New Delhi opposes terrorism in all its forms and manifestations," the statement said.

President of Kazakhstan Nursultan Nazarbayev also extended his condolences on Monday in a message to his Chinese counterpart Xi Jinping, according to the country's presidential press office.

"I want to emphasize that there are no excuses for crimes against humanity," Nazarbayev said in his message. "The international community must work together to neutralize these threats."

At the opening of the annual session of the National Committee of the Chinese People's Political Consultative Conference (CPPCC) on Monday, Chinese leaders and political advisors paid silent tribute to the victims of the incident.

"The CPPCC supports the law enforcement departments to crack down on all violent, terrorist and criminal activities in accordance with law," said Du Qinglin, vice chairman of the CPPCC National Committee.

Chinese police said on Monday three suspects involved in the terror attack had been captured.

The Ministry of Public Security said the terrorist gang led by Abdurehim Kurban was responsible for the attack.

The health authorities said 20 of the 143 injured in the attack were still in critical condition.