Gunmen on Friday killed two police officers who were assigned to protect a team of polio workers in northwest Pakistan, Pakistan’s Local police officer said today . Local police officer Khalid Iqbal said the two officers were attacked as they headed to the town of Swabi on a motorcycle to protect the polio workers. Swabi lies 100 kilometers , northeast of Peshawar, the capital of Khyber Pakhtunkhwa province. The attackers then fled the scene. No group claimed responsibility, but Pakistani militants have killed more than a dozen polio workers and police protecting them over the past year. They accused health workers of acting as spies for Washington and claim the polio vaccine is intended to make Muslim children sterile.(