Knife injured four foreign tourists and four local in an attack in the Jordanian city of Jerash.
Among the injured were three Mexicans and a Swiss citizen. One Mexican and a Jordan tour guide were seriously injured, the health minister said.
The suspected attacker was arrested nearby by police.
Jerash, home to a well-preserved Roman site, attracts thousands of foreign visitors each year.
Videos on social media show one woman lying bleeding on the ground and another woman in a blood-stained shirt.
Jordan's Health Minister Saed Jaber told reporters that all the injured were taken to a local hospital within 1
"The bleeding is stopped, the situation is controlled and both cases are stable," said Mr Jaber.
An American tourist, Marco Junipero Serra, told the BBC that the man who carried out the attack was dressed all in black and his face was covered in a mask.
The attacker leaped over the fence at about 11:00 (09:00 GMT) and began indiscriminately stabbing people, Mr Serra said.
According to him, the police did not close the site during the incident and people are still free to enter and leave.
One of the injured was Ali El Agrabawi, the driver of a tourist bus. At a hospital in Jerash, he told reporters he had been stabbed while trying to stop an attacker from entering a café full of tourists.
Jordan, viewed as a relatively safe destination, is highly dependent on its tourism industry.
According to the tourism council of the country, the country has 21,000 archeological and historical sites.