KUALA LUMPUR (AFP) - Malaysia has deported a suspected Sikh militant wanted for the 2009 killing of an Indian politician, police said Thursday.

The man, 36, using a fake Nepalese passport, was arrested in southern Malaysia on October 24 for immigration offences and deported Wednesday, federal police chief Khalid Abu Bakar said in a statement.

He is alleged to be part of a Sikh militant group responsible for the 2009 killing of Indian politician Rulda Singh.

Singh was a former president of Sikh hardline group Rashtriya Sikh Sangat, which supports the Hindu nationalist grassroots organisation linked to India's ruling Bharatiya Janata Party.

Khalid said Malaysian authorities cooperated with their Indian counterparts to make the arrest, bringing to six the total number of militants believed to be linked to the group held since 2009.

In recent months they have also arrested dozens of Malaysians over suspected links to Islamic State in Iraq and Syria (ISIS).

Three were charged last month for allegedly attempting to leave Malaysia to join ISIS.

At least 40 Malaysians are believed to have left for Syria amid rising concern over the appeal of ISIS in the country.

Earlier this year, police also arrested and deported several suspected Tamil Tiger separatists to Sri Lanka.

They included at least two with refugee status, prompting criticism from the United Nations refugee agency.