Blackfriars accident - lorry/tree?

We just saw what looked like a Royal Mail lorry hitting a low tree at the junction to the south of Blackfriars Bridge. My wife thought she heard someone cry for help. We hoped no-one was hurt - we were on the other side by Doggetts so we decided not to investigate since plenty of people were closer and able to help if necessary. Does anyone know more? With any luck it only involved the lorry and the tree and not a pedestrian or cyclist.

Everyone is ok http://twitter.com/#!/Ldn_Ambulance/status/106277247056494592

The planes do seem susceptible to losing branches at the minute. The impact of the lorry didn't sound much louder than when the buses used to hit the low trees on Waterloo Road, and they tended to just bounce off.