A 28-year-old Indian girl returning from Frankfurt, Germany and a 24-year-old boy back home from Detroit, the United States, have been quarantined after they were found to have suspected A/H1N1 flu symptoms upon arrival Sunday night, said local media reports on Monday.

The two are now confined at an airport quarantine facility at the Indira Gandhi International airport in New Delhi.

Meanwhile, nasal and throat samples of the two patients have been sent to National Institute of Communicable Diseases in Delhi and National Institute of Virology in Pune, western India, for testing, said the reports.

A passenger from the United States to Hyderabad has been tested negative by Monday morning, said health authorities, who claimed that so far India is free from the A/H1N1 flu virus.

Indian health authorities have been screening of passengers coming from affected countries at 21 major international airports across the country.