An Afghan poisoning sent 160 schoolgirls to a hospital in Takhar province on Tuesday, the third incident of its kind in recent weeks, CNN reported.
Officials suspect the classrooms might have been sprayed with a toxic material before the girls arrived, in an attempt to keep the young women from attending class, CNN reported.
The Taliban denied carrying out such poisoning attacks over the weekend, but BBC News correspondents say that local Taliban groups acting independently have admitted responsibility for some of them.
"The Afghan people know that the terrorists and the Taliban are doing these things to threaten girls and stop them going to school," police spokesman Khalilullah Aseer said last week, according to CNN. "That's something we and the people believe. Now we are implementing democracy in Afghanistan and we want girls to be educated, but the government's enemies don't want this."
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The schoolgirls, aged between 10 and 20, were taken to the hospital after complaining of headaches, dizziness and vomiting, Hafizullah Safi, director of the provincial health department, told CNN. The health department collected their blood samples, which are being sent to Kabul to be tested.
Reuters reported that over 120 schoolgirls and three teachers were poisoned last week. In April, 170 girls were taken to the hospital after suffering a similar incident.
Also last week, Afghanistan's Ministry of Education said that 550 schools in 11 provinces where insurgents maintain a strong presence have been shut down, according to Reuters.
Afghan girls were not allowed to attend school over the course of the Taliban's rule, from 1996 to 2001, CNN reported. However, schools reopened after the regime was toppled in 2001 by the US-led coalition's invasion.
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