My father after becoming US Citizen moved back to India for health reasons. My mother holds a Green card but had to follow him. I am supporting them and sending money via bank account. They do not have any other income. In the past I did claim them as dependents, but now since they are out of the country for more than an year, can I claim them as my dependents? I am a US citizen as well.

Appreciate your answer.

Thanks

You can claim your parent as dependent (qualifying relative) if
1. You provided more than half of their support, and
2. the parent did not earn more than $3,500 in 2008.
It is not required that the parent live with you. Read about Qualifying Relative: : Your U.S. Tax Return: Requirements for claiming a dependent

Agreed!

The fact that your father is a U.S. citizen and your mother is a green card holder means they do NOT have to meet the Substantial Presence Test for time spent IN the U.S.