Spectra of protons of energies between 50 and 145 MeV emitted from carbon have been measured at angles from 105° to 160° with respect to the 640 MeV proton beam. The measurements have been carried out both inclusively and in coincidence with protons emitted at forward angles up to ±40° with energies from 255 MeV to 330 MeV. This energy interval has been chosen in accordance with the kinematics of quasifree scattering on two-nucleon groups. Inclusive differential cross sections at 140° and coincidence cross sections at the angle pair (− 12°, 122°) have also been measured with Be, Al, Cu and Pb targets. The data have been compared with the predictions of several models.