A police officer was killed while the driver of the van sustained serious injuries in a firing incident that took place in Bannu area of Khyber Pakhtunkhawa, TV channels quoting police reported on Friday. According to details, unknown outlaws opened fire and killed a police officer travelling by police van while the driver was also injured. Police rushed to the site and shifted the police personnel identified as Saeed Rehman to nearby hospital. Police have cordoned off the area to trace the culprits behind this killing. No arrest was made so far till the filling of this report.