The 50 meter long tanker-barge Conzelo sank in early morning hours while moored in the outer harbor in Hansweert, Zeeland, Netherlands.  The master with his two sons on board were able to abandon ship in time.   One son was still asleep and had to leap into the water before the Conzelo went down.   No one was injured.   The vessel was loaded with cement and now rests 9 meters below water.  Authorities are conducting an investigation into the incident.   The vessel does not block or hinder traffic in the harbour.