Pakistan security forces arrested a suspected Taliban mastermind on Thursday, Fox News has learned.

Mohtasim Agha Jan is thought to be a chief Taliban political strategist in Karachi.

"He is a close aide of spiritual leader Mullah Omar and ranked number seven on the post 9/11 watch list," a U.S. intelligence official told Fox News.

His arrest may be due in part to the CIA's interrogation of suspected terrorist Abdul Ghani Baradar, who was arrested in early February.

After the arrest of Ghani Baradar, Mohtasim Agha Jan's name surfaced in discussions about who might replace the Afghan Taliban's No. 2.

He is a former Taliban finance minister who is reported to have family links to Taliban leader Mullah Omar. As a government official, he had the power to control the flow of money and appoint deputy ministers. He was born in the late 1960s in Kandahar city.

The arrests have been hailed by U.S. officials and many analysts as a major blow to the Taliban in Afghanistan, though they caution that the group has rebounded from the death or detention of previous leaders.

Opinion is divided on whether the crackdown signals that the country's powerful intelligence forces are adopting a harder line against the militants.

The United States has long demanded Pakistan take action against the group, which critics say have long enjoyed relative sanctuary in Pakistan.

Some experts say the arrests may be aimed at removing moderates within the Taliban who were considering taking part in possible reconciliation talks with the Afghan government.

Earlier, Interior Minister Rehman Malik said he had no information on the arrest of Mohtasim. Afghan Taliban spokesman Qari Yousef Ahmadi denied he had been arrested.

There had been speculation that Mohtasim was in the running to replace Baradar, who was reportedly arrested in a joint raid with American intelligence officials.

Born in the late 60s, Mohtasim was considered close to Taliban leader Mullah Omar. He was not known to be among the most hardline group within the Taliban.

Earlier Thursday, dozens of militants attacked a security checkpoint in the northwest close to the Afghan border, sparking a gunbattle that left 30 insurgents and one soldier dead, officials said.

The battle occurred overnight in the Chamarkand area of the Mohmand tribal region, said government and military officials, speaking on condition of anonymity because they were not authorized to talk to the media.

Chamarkand borders the Bajur tribal region, where the army said Tuesday it had finally defeated Taliban and Al Qaeda militants after more than a year and a half of fighting.

Washington has praised Pakistan for its recent military operations but wants the government to do even more to target militants using its territory to stage cross-border attacks against U.S. and NATO troops in Afghanistan.

The Associated Press contributed to this report.