> Surviving Mumbai gunman with India

The lone surviving gunman in the deadly Mumbai attacks was to appear before an Indian judge on Thursday so his detention for questioning can be extended.

The militant, Mohammed Ajmal Amir Iman, will receive an "extension of his remand," said Mumbai police chief Hassan Gafoor, who gave no further details, citing security concerns.

The officer in charge of the investigation, Mumbai crime branch chief Rakesh Maria, said he was unlikely to be shifted from the secret location where he is being interrogated.

"We have asked the magistrate to come to the crime branch in view of the security situation," he said.

He said that investigators were still finalising charges against Iman, including "making war against the country, murder, attempted murder and other charges under the arms and explosives act."

Iman, identified by Indian authorities as a Pakistani national, was one of 10 heavily-armed Islamist militants who killed 163 people across the financial capital Mumbai, including at two luxury hotels and the main railway station.

He was arrested on the first evening of the attacks, which transformed Mumbai into a battle zone from late on Nov 26 until Nov 29.

According to police, Iman, from Okara, in Pakistan's  Punjab province, took part in the killing spree at Mumbai's main railway station.

Pakistan raided camp in Kashmir

Indian officials say the group were trained and sent by Lashkar-e-Taiba (LeT), a militant group based in Pakistan and viewed by some as a creation of Pakistan's military spy agency, the Inter-Services Intelligence (ISI).

Under intense international pressure, Pakistan launched a major operation over the weekend against militant organisations in the country, raiding a camp in Kashmir run by a charity linked to LeT and arresting 15 people.

Pakistan's Prime Minister Yousuf Raza Gilani said authorities there had arrested two senior LeT members - Zaki-ur-Rehman Lakhvi and Zarar Shah, both named by Indian media as suspected planners of the Mumbai attacks.

But the United States said it still wanted to see Pakistan adopt a tougher stance towards the group.

"What we are looking to see is if there's going to be a shift in Pakistan in how they deal with LeT," said White House spokeswoman Dana Perino.

"If it proves out, over time, that there is that shift, then that would be a good one, and something that we would welcome. But it's just too early for us to say," she told reporters.

The top US military chief applauded Islamabad's response since the Mumbai siege.

"They've moved pretty quickly with respect to these arrests, with respect to shutting down some of the camps, and all that, I think, is very positive," said chairman of the Joint Chiefs of Staff Admiral Michael Mullen, who visited India and Pakistan last week.

India warned after the attacks that it was keeping all options open in dealing with Pakistan.

India and Pakistan - both nuclear-armed - have fought three wars since independence from Britain in 1947 and nearly came to a fourth in 2001 after an attack on the Indian parliament that was also blamed on the LeT - Malaysiakini.