Sana'a, Yemen  - Yemen on Wednesday identified four more confirmed cases of H1N1 flu in students who have returned from an exchange programme in the United States, the official Saba news agency reported.

The four patients were among 32 students who arrived from the United States on Saturday after attending a student exchange programme, the agency quoted Health Minister Abdul-Kareem Rasea as saying.

Rasea announced on Tuesday that only one of those students was confirmed to have contracted the virus. The new cases bring the number of confirmed cases in Yemen to five.

He said three of the infected students live in the southern port city of Aden and the two others live in the capital Sana'a.

"They were given treatment and they are recovering," the minister said.

On Sunday, two US citizens were tested at a hospital in Sana'a over suspicion of having swine flu, but their tests were negative.

The H1N1 virus first emerged in the United States and Mexico in April, and has since spread internationally.

In the Middle East, cases appeared in Bahrain, Egypt, Israel, Jordan, Kuwait, Lebanon, Morocco, Qatar, the Palestinian territories, Saudi Arabia and the United Arab Emirates.(dpa)