Schools in Pakistan were struggling to return to normalcy this week after gunmen killed more than 20 people at Bacha Khan University in Charsadda on Jan. 20. Authorities closed dozens of schools Thursday over concerns their security systems weren't tight enough, while the New York Times reported Friday some parents were considering keeping their children home due to severe weather and continued threats.

"There is a scare across the country, and school authorities are not taking any chances," Mirza Kashif, the president of the All Pakistan Private Schools' Federation, told the Hindustan Times.

The Pakistan Taliban was rumored to be behind the Jan. 20 attack on Bacha Khan, which has about 3,000 attendees. Fighters swarmed the campus, forcing the evacuation of more than 200 students and injuring more than 50. The massacre came about a year after the militants killed 145 people, most of them children, in nearby Peshawar, CNN reported.

Afterward, Charsadda officials closed all government-run schools and Army Public Schools in the area until Monday. The government in Punjab canceled classes as well — citing near-freezing temperatures, not security issues. Rawalpindi also shut its schools down and sent notices to more than 50 institutions it said were not safe enough. Bacha Khan itself reopened, then closed indefinitely. 

Though one Taliban spokesman has distanced the group from the Bacha Khan attack, Pakistan Taliban leader Umar Mansoor recently appeared in a video promising more violence. "Now we will not kill the soldier in his cantonment, the lawyer in the court or the politician in parliament but in the places where they are prepared: the schools, the universities, the colleges that lay their foundation," Reuters reported Mansoor said. "With the mercy of god, our attacks on all universities and schools will continue."

But at least one public official has spoken out against closing schools in Pakistan. Interior minister Chaudhry Nisar Ali Khan told the media Thursday that the threats to educational institutions were minor and didn't warrant such widespread shutdowns.

"We cannot close our businesses and schools," he said, according to the New York Times. "This is what the militants want."