Big progresses have been achieved in the measurements of cosmic rays and gamma rays in recent years. The diffuse $\gamma$-ray emission above 100 TeV was measured by the Tibet-AS$\gamma$ experiment. Hardenings of the boron-to-carbon and boron-to-oxygen ratios at about 100 GeV/n have been revealed by the DAMPE experiment. These observations indicate modifications to the traditional cosmic-ray propagation and/or interaction model. In this contribution, we propose that the secondary particles produced by the hadronic interactions of freshly accelerated cosmic rays with the interstellar gas near the sources, can naturally account for the diffuse emission and the secondary-to-primary ratios. This model can be further tested by recent measurements with LHAASO.