The German Defense Ministry says experts are assessing whether any serious damage was done to one of its submarines after its rudder touched the ground as it was leaving a Norwegian harbor.

The ministry said Thursday that divers have taken photos of the ship's rudder and it shows no visible signs of damage, but that it is standard procedure to evaluate the seaworthiness of a vessel while it is docked after such an incident.

The ministry says the Type 212A diesel-electric submarine grazed the ground Tuesday as it was going backward at slow speed, executing a turn as it was departing the Haakonsvern harbor. It has now re-docked in the harbor for inspection.

Germany regularly conducts deep water trials off of Norway.