BALTIMORE (AP) — Salvage crews at the site of the collapsed Francis Scott Key Bridge in Baltimore are turning their focus to the thousands of tons of debris sitting atop the Dali, a massive cargo ship that veered off course and caused the deadly catastrophe last month.

An estimated 3,000 to 4,000 tons of steel and concrete landed on the ship’s deck after it crashed into one of the bridge’s supporting columns and toppled the span, officials said at a news conference Friday. Crews will have to remove all that before refloating the stationary ship and guiding it back into the Port of Baltimore.

Officials displayed overhead photos of the ship with an entire section of fallen roadway crushing its bow.

So far, cranes have lifted about 120 containers from the Dali, with another 20 to go before workers can build a staging area and begin removing pieces of the mangled steel and crumbling concrete. The ship was laden with about 4,000 containers and headed for Sri Lanka when it lost power shortly after leaving Baltimore.