The United Nations, as well as rights groups, have criticised the arrest of a prominent activist in Indian-occupied Kashmir on terror funding charges.

Khurram Parvez was arrested late on Monday by India's federal National Investigation Agency (NIA), an Indian official briefed on the situation told Reuters.

His residence and office were searched and a mobile phone, laptop and books seized, he added.

A spokesperson for the NIA confirmed Parvez's arrest on Tuesday.

He is being held under the Unlawful Activities (Prevention) Act, which allows for the detention of up to six months without trial.

His lawyer, Parvez Imroz, could not immediately be reached for comment.

Mary Lawlor, the UN Special Rapporteur on Human Rights Defenders, called Parvez's arrest “disturbing”.

“He's not a terrorist, he's a human rights defender,” she said in a tweet.

Parvez, one of Kashmir's best-known activists, is head of Jammu Kashmir Coalition of Civil Society, a group of rights organisations working in the region.

He was arrested and detained on similar charges in 2016, after being prevented from boarding a flight to attend a UN human rights forum in Geneva. He was eventually released without being convicted of any crime.

India has long faced allegations of rights abuses in the occupied territory — charges that New Delhi deny.

It tightly controls access to occupied Kashmir for foreign observers, including the UN.