"We never expected that Afghanistan will be returning to the stone age," said ANIM's founder Ahmad Sarmast, adding that Zohra orchestra represented freedom and female empowerment in Afghanistan and its members served as "cultural diplomats".
Sarmast, who was speaking from Australia, told Reuters the Taliban had barred staff from entering the institute.
"The girls of Zohra orchestra, and other orchestras and ensembles of the school, are fearful about their life and they are in hiding," he said.
A Taliban spokesman did not immediately respond to questions about the status of the institute.
Since returning to power as the final Western soldiers withdrew from the country, the Taliban have sought to reassure Afghans and the outside world about the rights they would allow.
The group has said cultural activities as well as jobs and education for women would be permitted, within the confines of sharia and Afghanistan's Islamic and cultural practices.
INSTRUMENTS LEFT BEHIND
While Khpalwak frantically burned her musical memories on Aug. 15, the day the Taliban marched into Kabul without a fight, some of her peers were attending a practice at ANIM, preparing for a big international tour in October.
At 10 a.m., the school's security guards rushed into the rehearsal room to tell the musicians that the Taliban were closing in. In their haste to escape, many left behind instruments too heavy and conspicuous to carry on the streets of the capital, according to Sarmast.
Sarmast, who was in Australia at the time, said he received many messages from students worried about their safety and asking for help. His staff told him not to return to the country because the Taliban were looking for him and his home had been raided several times.
The dangers facing performers in Afghanistan were brutally highlighted in 2014, when a suicide bomber blew himself up during a show at a French-run school in Kabul, wounding Sarmast who was in the audience.
At the time, Taliban insurgents claimed the attack and said the play, a condemnation of suicide bombings, was an insult to "Islamic values".
Even during 20 years of a Western-backed government in Kabul, which tolerated greater civil liberties than the Taliban, there was resistance to the idea of an all-female orchestra.
Zohra orchestra members have previously spoken about having to hide their music from conservative families and being verbally abused and threatened with beatings. There were even objections among young Afghans.
Khpalwak recalled one incident in Kabul when a group of boys stood attentively watching one of their performances.