Pakistan authorities on Wednesday arrested Hafiz Saeed, the alleged mastermind of a four-day militant attack on Mumbai in 2008, on terror finance charges, a spokesman for the chief minister of Punjab said.

The move came days before a visit to Washington by Prime Minister Imran Khan, who has vowed to crack down on militant groups operating in Pakistan.

Saeed, designated a terrorist by the U. S., is the founder of Lashkar e Taiba (LeT), or Army of the Pure, a militant group.

The LeT was blamed by the United States and India for the Mumbai attacks, which killed more than 160 people.

Saeed has denied any involvement and said his network, which includes 300 seminaries and schools, hospitals, a publishing house and ambulance services, has no ties to militant groups.

A spokesman for Punjab Governor Shahbaz Gill said Saeed was arrested near the town of Gujranwala in central Pakistan.

“The main charge is that he is gathering funds for banned outfits, which is illegal,” the spokesman said.

Pakistan, which is included on the so called “gray list” of the Financial Action Task Force, a money laundering and terror finance watchdog, has been under increasing pressure to stop the financing of militant groups.

The United States has offered a 10 million dollars  reward for information leading to Saeed’s conviction over the Mumbai attacks.