A radical cleric suspected by the US of orchestrating the 2008 Mumbai attacks has been arrested in Pakistan, days before Prime Minister Imran Khan is due to meet Donald Trump in Washington.
Hafiz Saeed has a $10 million (Dh36.7m) bounty on his head and was taken into custody in Punjab province while travelling from the eastern city of Lahore to Gujranwala.
The founder of the Lashkar-e-Taiba group is one of the world's most wanted terrorist suspects and Pakistan's failure to put him on trial has poisoned relations with the US and India.
Pakistan has faced increasing pressure to take action, along with the threat of international sanctions if it fails to tackle terrorism financing and money laundering.
It recently registered more than a dozen cases against Saeed and his associates, accusing them of using charitable fronts to raise money destined for banned militant groups.
Saeed, 69, has been detained before and has spent time under house arrest, but he has never been charged or put on trial.
In recent times, he has been free to hold rallies and oversee his charitable foundations, which the US and India say are fronts for Lashkar-e-Taiba.
An Indian government official told Reuters that arresting Saeed was not enough and he should be tried and convicted.
"We want real action, not these kinds of steps that are reversible," the official said. "One court orders his arrest, another frees him."
He said the arrest appeared to be for America's benefit.
“We have seen this before. After the visit is over, things are usually back to what they were before."
The US Treasury wanted notice says Saeed, a former Arabic and engineering professor was suspected of organising “terrorist attacks including the 2008 Mumbai attacks, which resulted in the deaths of 166 people including six American citizens”.
His spokesman, Nadim Awan, told AP that the cleric had split with Lashkar-e-Taiba in 2001 and had no links with the organisation since. The group was banned in 2002.
Pakistan has long been accused of sponsoring and harbouring militants for foreign policy influence in Kashmir, India and Afghanistan.
Refusal to take action against militant proxies on its soil has been one of the main irritants in the relationship between Islamabad and Washington.
Crackdowns have been conducted under international pressure before, but have appeared half-hearted or cosmetic.
Islamabad announced a new purge this year after a suicide bombing claimed by Jaish-e-Mohammad, based in Pakistan, took it to the brink of war with India.
Jamaat-ud-Dawa which calls itself a humanitarian organisation, but which the US, Britain and the UN recognise as a front for Lashkar-e-Taiba, was banned in that purge.
The government has taken over schools, mosques, seminaries and properties linked to Saeed's charities.
A spokesman for Punjabi Governor Shahbaz Gill said the main charge against Saeed was that he was “gathering funds for banned outfits, which is illegal".
Analysts believe Pakistan may have also been forced to act by the threat of international financial sanctions.
Pakistan is on the Financial Action Task Force's grey list, because of concerns that it is a haven for money laundering and terrorist cash.
The country has until October to take persuade the force that it is cleaning its act up or it faces being blacklisted, which could badly dent investment as the country suffers an economic crisis.
Shah Mehmood Qureshi, Pakistan's Foreign Minister, said he hoped Mr Khan’s first trip to the White House would help to reset ties after years of acrimony.
Mr Qureshi said he hoped it would shift US policy from “coercion” into “co-operation”.