Taliban gunmen are warning Christians in Kabul that they are being watched.
The London Independent reports the warning comes after a Christian aid worker was killed Monday on her way home from work.
Taliban gunman say they killed 34-year-old Gayle Williams, because she was converting people away from Islam.
A police spokesman in Kabul says they are trying to protect Christians and warning them to "be vigilant."
Proselytizing is against the law in Afganistan.
Other Christian missionaries and charities have faced severe hostility there.
Sources: CBN News, London Independent
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