A man filming an assault with his cellphone camera at bustling Fifth and Market streets Wednesday was punched and robbed of the phone, police said.

The victim began filming as four thugs — one as young as 13 — attacked a 48-year-old woman around 6:40 p.m. One of the crooks, a man in his late teens to early 20s, punched the victim and swiped his phone, police said.

The cellphone thief and the phone were not recovered. However, two of the other suspects — the 20-year-old man and the 13-year-old, were subsequently arrested, police said.

Neither victim was seriously injured. Police are hunting the two other thugs.

maldax@sfexaminer.com