Four Iowa Cornell College instructors were taken to hospital after a "serious incident" during a daytime attack by a 55-year-old man in the northern province of Jilin.
Iowa Representative Adam Zabner said his brother, David, was one of the four instructors injured in what he described as a stabbing.
China's foreign ministry said that none of those injured were in a life-threatening condition.
Police said an assailant with the surname Cui clashed with one of the Americans and then stabbed the person. He went on to injure three other US visitors and a Chinese tourist who tried to come to their rescue.
Mr Zabner said the group of instructors had been visiting a local temple on Monday when they were attacked by a man with a knife.
He said his brother had been stabbed in the arm at Beishan Park in Jilin city and was recovering well in hospital.
Cornell College said the four instructors had been teaching "as part of a partnership with a university in China". The group had been accompanied by a member of Beihua University at the time of their visit to the park on Monday.
China's foreign ministry spokesperson Lin Jian said that police believed the attack was "an isolated incident" and that China was "one of the safest countries in the world".
"We believe this will not damage relations with other countries," he added.
National security adviser Jake Sullivan said on X/Twitter that the US was "deeply concerned" by the stabbing.
"Our team has been in touch with these Americans and our PRC counterparts to ensure that the victims’ needs are met, and appropriate law enforcement steps are being taken," he said. "We wish them a speedy recovery."
Iowa Governor Kim Reynolds said that she was in contact with the department about the “horrifying” attack.
Images of the incident circulating online appear to show at least three people bleeding and lying on the ground.
However, the pictures appear to have been quickly censored on China's internet.
On Tuesday, searches for terms such as "foreigners Jilin" produced no results despite the search term trending on Weibo.
Internet users instead resorted to discussions under adjacent topics while some were also seen asking for more information about the incident.
There are also few reports about the incident in Chinese state media.
Lewis Musonye
