How they exfiltrated footage of the 1989 massacre is an interesting story in its own right. The AP photojournalist who captured (among others) Tank Man couldn't safely walk the streets, so he recruited a random tourist to smuggle his film rolls, in his underwear, from the hotel to the AP's press office.

> [Jeff Widener] "I had earlier accomplished my mission of photographing the occupied Tiananmen Square so I gave all my rolls of film to Kurt/Kirk who smuggled it back to the A.P. office in his underwear. The long-haired college kid was wearing a dirty Rambo T-shirt, shorts and sandals. Security would never suspect him of being a journalist."

https://archive.nytimes.com/lens.blogs.nytimes.com/2009/06/0...

From the AP office, it was scanned (?) and exfiltrated with a dial-up modem, over copper telephone landlines (unsure of the technology. 1980's gadgets).