Sergio Moyane, a district administrator in the capital Beira, said: "We are facing a serious flooding drama.
"There are many houses under water and many fields have been swamped."
"Because of the communication problems we are still looking for people either stranded or injured"
Casmiro Abreu, spokesman for INGC's emergency operation centre
South Africa and the European Union on Saturday both pledged more help for the relief effort.
Casmiro Abreu, a spokesman for the emergency operation centre run by Mozambique's national relief agency INGC, said: "Because of the communication problems we are still looking for people either stranded or injured."
Officials were seeking to help 36,000 people in the area who lost virtually all their possessions.
Rescue
Abreu said: "We are currently distributing a little amount of food which we have and building toilets."
Tourists were airlifted on Friday from hotels in the Bazaruto archipelago, a string of islands 40 km off the coast in the Indian Ocean dotted with luxury resorts.