YONKERS - Police are urging boaters to remain alert as more barges are placed in the Hudson River for a new Tappan Zee Bridge dredging project.

The warning comes after bride-to-be Lindsey Stewart and would-be best man Marc Lennon were killed when the boat they were on crashed into a barge. The victims' families say the barge was not properly lit.

Rockland County Sheriff Marine Unit Sgt. John Murphy says boaters should still be cautious, no matter how many lights are on the barges.

"Slow speeds if you're unsure what's out there," Murphy said. "Always wear your life jacket."

Murphy says boaters should refrain from going out on the water at night or at times of low visibility.

The Rockland County Sheriff's Department and the New York State Police are expected to wrap up their investigation into the fatal boat accident next week.