Tampering of luggage

My parents and I checked our bags in on the British Airways flight to Durban on Sunday ( BA6313 for departure at 17:30). Upon arrival at King Shaka airport, at baggage carousel 2, I noticed that the flaps of my bag were open and that the cable ties that i had used to secure my zips had been removed and that the zip was broken. Once home, I opened the bag to find that my vanity case had been opened and the contents strewn about the bag. There was also another bag that had been opened along with the vanity bag and was very obviously searched as all its zips were open and the pockets were inside out. A few pieces of costume jewellery and some coins were missing. Very disappointing and disheartening experience from otherwise good treatment by the airport and the airline.