Authorities are hunting for clues in Pakistan to determine if Tashfeen Malik had ties to hard-line Islamist clerics or institutions. (The Washington Post)

Authorities in Pakistan and the United States are trying to determine whether the woman who carried out last week’s terrorist attack in California had ties to other hard-line Islamist clerics or institutions here besides the conservative madrassa she attended while in college.

Nearly one week after Tashfeen Malik and her husband killed 14 people in San Bernardino, Calif., it appears that Malik’s path toward Islamist extremism began while she was a pharmacy student in Pakistan from 2007 to 2013 and not during her childhood in Saudi Arabia.

FBI Director James B. Comey said Wednesday on Capitol Hill that Malik and her husband, Syed Rizwan Farook, 28, had been communicating online and discussing jihad at least two years before they opened fire in California.

Investigators here are trying to determine whether the 29-year-old Malik was radicalized near her university in southern Punjab province, which at the time was a hotbed of Islamist militancy, or whether her travels took her to other areas of Pakistan.

She also could have been radicalized online; some acquaintances have said she spent considerable time on the computer.

Piecing together Malik’s history in Pakistan is proving difficult, since security and intelligence officials are pressuring people who had contact with her not to speak to the media.

Officials at the Al-Huda Institute confirmed this week that Malik had enrolled in classes at one of their madrassas in Multan between 2013 and 2014. The Canada-based institute teaches Islamic studies to women and is aligned with the particularly conservative Wahhabi interpretation of Sunni Islam.

Institute officials have stressed that they doubt Malik’s studies there are responsible for her radicalization, and her teachers and former classmates at Bahauddin Zakariya University in Multan remember her as shy and polite. Investigators are now trying to determine what other contacts Malik may have established in Pakistan with religious figures who influenced her in the years leading up to the San Bernardino attack.

On Friday, when news broke that Malik was born in Pakistan but raised in Saudi Arabia until she returned to this country for college, one man who identified himself as her uncle said in an interview that she had developed an interest in the controversial Red Mosque in Islamabad and its cleric, Maulana Abdul Aziz.

In 2007, the mosque was the site of a bloody government crackdown against Islamic student radicals that helped lead to the creation of the Pakistani Taliban.

But the man’s neighbors say he left the village near Malik’s ancestral home town over the weekend and has not been seen since.

“The entire family disappeared somewhere,” said one of the residents of the village, who asked not to be identified out of concern for his safety. “The house is locked from the outside. . . . I don’t have any idea whether he was picked up by security agencies or he, himself, went into hiding.”

Another student who attended Bahauddin Zakariya University, who also asked not to be identified for the same reason, said Malik had spoken about attending sermons Aziz gave while traveling near her parent’s home town in the Layyah district of Punjab province.

Federal law enforcement officials in the United States have said they are investigating reports that Malik may have had an affiliation with the Red Mosque. But Pakistani security officials say they have uncovered nothing to suggest Malik had ever attended any of Aziz’s sermons or had any contact with any of the mosque’s affiliates.

“The information that we have so far doesn’t show any link or contact,” said one Pakistani intelligence official, who asked for anonymity to freely discuss the matter.

Another senior Pakistani intelligence official said Wednesday that investigators still believe Malik was radicalized “elsewhere.”

Even if Malik never had any association with Aziz or his teachings, investigators are not ruling out that she may have had contacts with other radical Islamist clerics or groups here.

“Malik was a religious girl; she used to meet many clerics for the sake of knowledge,” Hifza Batool, who identified herself as one of Malik’s aunts, said in an interview over the weekend in her home town of Layyah.

Saifullah Mehsud, executive director of the Fata Research Center, said the proximity of Multan to a number of hard-line Sunni militant groups should be worrying to investigators. Many are affiliated with the Deobandi sect of Islam, from which groups such as the Taliban have historically found their greatest sources of support.

“The biggest concentrations of madrassas of Deobandi are in southern Punjab,” Mehsud said. He noted many of them are small and unregistered and difficult for authorities to monitor.

“According to the local population, these are the nurseries for militant recruitment,” he said.

One local security official in Multan, who requested anonymity because he was not authorized to speak to the media, said investigators are even exploring whether Malik had any contact with Malik Ishaq, the former commander of Sunni militant group Lashkar-e-Jhangvi.

Ishaq, who operated in southern Punjab, and his two sons were killed by Pakistani police in July. According to media reports, Ishaq was killed days before he may have been set to announce his allegiance to the Islamic State.

But a senior Pakistani security official said it was “utter nonsense” to think Malik could have had any contact with Ishaq.

During a visit to Islamabad on Wednesday as part of the multinational Heart of Asia conference, U.S. Deputy Secretary of State Antony J. Blinken said American officials are still trying to determine whether they should have more closely scrutinized Malik before issuing her a visa.

“As we uncover the facts and draw conclusions, it will be a lot easier to answer those questions,” Blinken said. “We are still learning about this.”

The Red Mosque, in a well-to-do section of Islamabad, is a particularly sensitive topic for Pakistan.

In the mid-2000s, Aziz was the spiritual leader of a student-led Islamist movement attempting to impose sharia law in Pakistan. The movement included hundreds of women, who became known as the “burqa brigade.”

In 2007, Pakistan’s ruler at the time, Pervez Musharraf, ordered a military operation against students who were holed up in the mosque.

More than 100 people were killed, including Aziz’s younger brother. Aziz was arrested, but he was released in 2009 and later acquitted. But there have long been suspicions that Aziz’s mosque remains a pipeline for militancy.

Officials here said the allegations about Malik’s ties to the Red Mosque appear to be just the recirculation of news reports that surfaced late last week when U.S. investigators first identified Malik as a Pakistani national.

Within hours, several stories appeared in the local and British media alleging that investigators had found photographs of Malik and Aziz together. Pakistan’s ARY News then reported that senior State Department officials had contacted Pakistani Prime Minister Nawaz Sharif to express concern about the alleged ties.

But Sharif and U.S. officials quickly denied that there had been such a discussion. ­Pakistan’s interior minister, Chaudhry Nisar Ali Khan, also blasted the reports as baseless.

Khan accused the media of trying to “defame” Pakistan by attempting to link Malik to the Red Mosque.

Aziz has also denied having any association with Malik.

“Our mosque does not support Islamic State, and connecting us with such an organization would be tantamount to hatching a conspiracy against us,” said ­Mufti Tahseen Ullah, an Aziz spokesman.

Farhan Jameel Malik, a cousin of Tashfeen Malik, runs a computer shop in Rawalpindi, near the capital. In an interview Wednesday, he said he does not believe Malik had ever visited Islamabad, much less the Red Mosque.

“This just seems to be a conspiracy to defame Pakistanis,” he said. “I’ve been here for the last 12 or 13 years, and she never came to visit us.”

Over the past year, Pakistan’s government has been under growing pressure from progressive Pakistanis to arrest Aziz or shut down his mosque.

Last December, Pakistani progressives were outraged when Aziz initially refused to condemn a Pakistani Taliban attack on a school that killed 157 teachers and students.

A video surfaced a year ago in which some female students — who claimed affiliation with a madrassa run by Aziz’s wife — pledged alliance to the Islamic State. Aziz quickly denounced the video.

Just a month ago, dozens of self-described members of the “burqa brigade” held a protest in Islamabad calling for “jihad” to bring about sharia law, according to Pakistan’s Dawn newspaper.

Craig reported from Islamabad. Adam Goldman in Washington contributed to this report.

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