MANORVILLE - A Manorville motorcyclist who killed his pregnant fiancee during an East End police chase has pleaded guilty.

Matthew Byank, 21, pleaded guilty today to second-degree manslaughter, according to Newsday.

Lauren Parris, 19, of Mastic Beach, was killed nearly two years ago. Parris was thrown from Byank's bike when he hit a utility pole in Amagansett. Prosecutors say Byank was fleeing police at speeds of up to 150 mph when he lost control.

A judge is expected to sentence Byank to no more than three to nine years in prison in July.

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