Happened to me on Monday night 9.30 pm walking on champion park road from Denmark Hill station, was on the way home. Same thing. young guy on a bike came up behind me and yanked my phone out of my hand. I screamed too but unfortunately he was off and phone is gone. Could still see it on the map about 10 mins walk from East Dulwich station, reported to police who essentially called me the next day to say nothing will be done. Just keep your phones close by and be aware of your surroundings folks, definitely people in the area are being targeted. Few passer bys saw it happens and nobody asked if I was ok which was fairly upsetting on top of it!