The RQ-4A Global Hawk drone crashed during a routine training flight from Naval Air Station Patuxent River, according to Jamie Cosgrove, a spokeswoman for the Unmanned Aviation and Strike Weapons Program at the base.

There were no injuries to civilians and no property damage, said the Navy, which said it is investigating the cause.

The crash, at about 12:11 eastern time, reportedly took place in a marshy area of the Nanticoke River, near Bloodsworth Island in Dorchester, Md., about 20 miles from the city of Salisbury.

The Broad Area Maritime Surveillance Demonstrator (BAMS-D) aircraft, a modified Air Force Global Hawk RQ-4, is operated from Naval Air Station Patuxent River, Md., as part of the overall BAMS development program. The aircraft is one of five aircraft acquired from the Air Force.

The first built-for-the-purpose MQ-4C BAMS is to be unveiled Thursday by Northrop Grumman at its facility in Palmdale, Calif. The Navy plans on acquiring more than a 100 of the aircraft, which are key to the service’s ability to keep watch on vast areas of ocean and land.