Pointing to the David Headley case as illustrative of the 'real threats from home-grown and international terrorists,' the US says it will continue working to disrupt, dismantle and defeat terrorism at home and abroad.

Commending various US agencies in getting a guilty plea from Pakistani American terror suspect David Headley for his role in planning the 2008 Mumbai terror attacks US Homeland Security Secretary Janet Napolitano said:

'As we have seen, we face real threats from home-grown and international terrorists.'

'And we will continue working to disrupt, dismantle and defeat terrorism at home and abroad to ensure the safety and security of the American people,' she said in a statement Thursday.

'I applaud the Department of Justice and the FBI for leading the effort culminating in today's guilty plea, and I commend the men and women of US Customs and Border Protection, US Immigration and Customs Enforcement and the DHS Office of Intelligence & Analysis who played critical roles as part of a true interagency investigation.'

Meanwhile, at the State Department spokesman Gordon Duguid discounted suggestions about India's disgruntlement over a feeling that Headley is getting off too lightly by pleading guilty.

'I wouldn't react to reports of their disgruntlement. It's a very large country, and I'm sure that there are a number of opinion centres in India on this issue,' he said.

Noting that it is an ongoing trial, Duguid said: 'What has been clear is that he has undergone a transparent and fair judicial process. And the United States Government will support the decision of our courts.'

The official said he was also not aware whether the State Department has received a request for access to David Headley's wife.