PSNI Chief Superintendent Stephen Cargin said he believes Pc Philippa Reynolds would have died instantly due to the force of the crash.
Ms Reynolds is believed to have been sitting in the rear driver's side seat when the unmarked police car was hit side on.
More top news
Moving footage of Manchester attack victim Saffie Roussous has been released as by her family as the youngster's took funeral place.
Brighter skies and blustery showers from the west.
UK tour operators can resume selling holidays in Tunisia for the first time since the Sousse massacre after a change in travel advice.