One person was killed and a second was critically injured Sunday afternoon when a Green Line light-rail train struck a vehicle that was on the tracks in St. Paul.

According to Metro Transit spokesman Drew Kerr, the eastbound train struck the vehicle near the Rice Street station about 4 p.m. One person in the vehicle died at the scene and a second was taken to Regions Hospital in critical condition.

The train operator was also taken to Regions for a medical evaluation, Kerr said.

The rail line between the Union Depot and Hamline Avenue stations was replaced with buses for a couple of hours as investigators did their work.

It was too early in the investigation to say how the vehicle came to be on the tracks, Kerr said.