Three students of the 14 returnees who arrived at Bangkok from Mexico on Sunday night have showed flu symptoms and are now quarantined in medical institute, director of the institute said on Monday morning.

According to Dr. Preecha Tantanakit, director of Bamrasnaradura Institute, blood test result would confirm whether the three students are infected with the A/H1N1 flu virus, which have been rampant in Mexico recently and killed at least 19, though Mexico said on Sunday its flu epidemic was declining.

The names of the suspected-flu-infected students were not disclosed.

Earlier report said only one of the students has a little fever, thought to be tired after a long journey and separated from others for further test.

The seven students and seven teachers, who visited Mexico under a scholarship since August last year, arrived from Mexico at Bangkok-based Suvarnabhumi International Airport around 11:30 PM on (GMT1630) Sunday, and were immediately taken to Bamrasnaradura Institute, the national infectious diseases referral hospital in Nonthaburi province north to Bangkok.