Received a bunch of photos via iMessage, now that message thread is frozen

Someone sent me a bunch of photos via iMessage in groups of 10-18 photos at a time. Now, that message thread is frozen. I can't text them, they can't text me. My screen completely freezes when I open that thread. Do I just need to wait until all of the photos "come through?" It's been 6 hours since they sent the photos... I've tried swiping up out of my messages and reopening; powering off and back on; volume up/volume down, hold side button until the apple appears; toggling the iMessage switch in Settings. Any other ideas I can try to unfreeze this message thread??