Security concerns
"We are all worried about security. I stay in my dorm during holidays because I am afraid the Taliban will kidnap me on the highway if I go home to my village," said Mohammed Amir, 22, a senior at Kabul University from Ghazni province who is studying language and literature.
"Everything is so unpredictable now," said Mursal Zohair, 19, who is studying software engineering on a US scholarship abroad but often comes home to visit friends at local colleges.
"You worry that someone will come and throw acid in girls' faces." Taliban militants have periodically targeted young women to deter them from studying, though mostly in rural provinces.
The American University campus is highly guarded and is not open or visible to the public behind high walls. Students there said they feel safe within the confines of the large compound, which is beside a major boulevard near the national parliament. But some worry that the kidnappings will deter other foreign instructors from coming there to teach.
The nonprofit, coed university, which opened in 2006, has about 1300 students.
It offers a full undergraduate curriculum, some graduate programmes and courses in English language proficiency. It has introduced a modern, Western-style model of higher education to the country, with competitive entry requirements and all courses taught in English.
Tuition fees are high by Afghan standards, at about US$190 per course credit, but many high-performing students receive scholarships.
"The university provides good security for us, and we feel safe inside. We are also part of Afghan society so we are familiar with the situation here, but we worry we may start losing our professors, that the foreign ones won't want to come back," said Sarah Mojda, 22, who is studying business administration.
Despite being reopened on Thursday, the campus looked almost deserted from the outside.
From time to time, small clusters of students hurried up to narrow red steel gates, showed their ID cards through a small grill, and were allowed to slip through an opening that quickly closed again. Journalists have not been given permission to visit since the abductions, and no university officials have given interviews.
Daoud Jalal, 20, a political science major from Ghazni, said he was worried that new foreign faculty members might decide it was not worth the risk. Those already here, he said, feel comfortable with the environment, but a new group is due to arrive soon after a summer break.
"Now we may have a difficult time convincing them that Afghan culture is welcoming," he said.
City a target
Kabul has long been targeted by Taliban insurgents, who periodically stage suicide bombings outside government and foreign facilities and assault vehicles used by the security forces. Recently, Islamic State militants have added to the quotient of violence, and two bombings in the past three weeks have set the city on edge.
On July 23, a massive suicide bombing claimed by Islamic State loyalists killed 80 people who were holding a peaceful demonstration in a public square.
On August. 1, a powerful truck bomb detonated outside a foreign guest house in the dead of night. The attack killed one policeman and sent shock waves through the sleeping capital.
The collapse of the foreign-backed war economy and soaring unemployment have also triggered a wave of street crime, especially armed robberies and kidnappings by organized criminal gangs, who sometimes "sell" their captives to the Taliban or simply demand ransom. Most victims are wealthy Afghans, such as money traders or importers, and the crimes are not widely publicized.
Abductions of foreigners are also becoming more common in the heavily policed capital, and they have a much more negative impact on Afghanistan's image among foreign investors and donors. An Indian aid worker with the Aga Khan Foundation, Judith d'Souza, 40, was kidnapped on a Kabul street on June 10 and is still missing.
Ahmad Muzzafari, an Afghan academic who teaches courses part time at the American University, said that even in a capital that has known violence through decades of war and years of insurgence, the growing phenomenon of kidnapping for money, as well as carjacking at gunpoint, has created a new sense of vulnerability among the population.
"Everyone is talking about the kidnappings. It is happening everywhere, and it is getting worse as the number of jobless people keeps going up," he said. "I am not a rich man, and I drive a 2006 car, but even that is enough to risk being abducted or killed for."
In the shadows
At Kabul University, a large and busy campus in a residential area, hundreds of students stroll on the surrounding sidewalks and police officers keep a low-key presence at the entrances. This week, most students had not heard about the kidnappings at the American University and said they were more worried about attacks and bombings by the Taliban.
But several faculty members there were keenly aware of the recent abductions and said they were keeping a careful eye out. Najib Mahmoud, a lecturer in political science, said he grew up in Kabul during the civil war of the early 1990s, when rival militia factions rocketed neighborhoods every night. "Back then I used to fear a rocket would kill me," he said. "Now I fear someone following me in the shadows."