reporter: tonight the israeli military publishing video of what it says is an operational tunnel inside the al shifa hospital complex. the idf has been operating around the complex for days, closing in on what they long asserted was a hub of hamas activity. ak-47s. we see handcuffs. reporter: doctors and health officials in the hamas-run enclave have denied those accusations. but this, the israeli military says and this is where they choose to hide everything. reporter: is part of the evidence they had promised as the idf continues its operation in the hospital complex that began early wednesday morning. it s not just the credibility of the idf and israel that s at stake. president joe biden says he feels absolutely confident hamas is there as the u.s. throws its weight behind israel. the first war crimes being committed by hamas by having their headquarters, their military hidden under a hospital. reporter: on thursday gaza again found itself under a total