"The US condemns this deplorable act of violence. Our thoughts are with the victims, their families and loved ones, and the Thai emergency personnel responding to the incident," National Security Council spokesperson Ned Price said.
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We will remain in close contact with the Thai authorities as they investigate this attack, Price said.
Secretary of State John Kerry also expressed his deep sympathy to all those affected by the explosion. In New York, UN Secretary General Ban Ki-moon hoped that those behind the attack would be brought to justice.
"The Secretary-General was shocked to learn of the explosion in Bangkok close to the Erawan shrine and the loss of life of innocent civilians," said a UN statement. "He expresses his condolences to the bereaved families and to the people and Government of Thailand, and wishes those injured a quick recovery," the statement said.
US is closely monitoring the situation and in touch with local authorities
"The US is closely monitoring the situation and liaising closely with local authorities to gather information to determine whether any US citizens were affected by the explosion," State Department Spokesman John Kirby said.
A US-based Hindu American Foundation said the attack "is an affront to the pluralistic ethos of Thailand's diverse society". "We urge the Thai police to conduct a thorough and swift investigation to find those responsible for this heinous attack," said Mihir Meghani, board member of the Hindu American Foundation.