WASHINGTON (AP) — District of Columbia police and Occupy DC protesters are offering conflicting accounts about a weekend incident in which a motorist struck three protesters near a downtown demonstration.Police said Saturday that a driver will not be charged for striking three people Friday evening near the city's convention center. Assistant Police Chief Lamar Greene said at a news conference Saturday night that police concluded from talking to two witnesses that the collision was unavoidable.But Heidi Sippel of Vandalia, Ohio, said that she and two family members were taking part in the demonstration when a silver Lexus sped toward them. Sippel said the driver slowed down, threw up his hands and then drove forward, hitting them. Police cited the three for obstructing traffic and walking against a do-not-walk sign, both of which carry fines.