3 killed after scaffolding collapses at 1,250-foot Miami TV tower The victims were contracted to upgrade a transmission antenna, WPLG reported.

 -- Three people died when scaffolding collapsed at a television tower in Miami today, ABC affiliate WPLG in Miami reported.

The 1,250-foot tower transmits the signal for the ABC affiliate as well as WSVN, another local station, WPLG reported.

WPLG assistant chief engineer Steve Ellis said the workers were removing gear at the top of the tower to install an upgraded transmission antenna for another station when the accident occurred. Ellis said the tower has been used by all the local broadcasters many times, describing it as "very, very safe."

"When they were removing this gear, pulling the second piece down, what they call a gin pole lifting device collapsed," Ellis said.

A witness told WPLG that the collapse sounded "like the wind from the hurricane."

"... And then when I heard the boom, I saw the debris fly in the air, and I immediately called 911," said Eric Garner.

The victims were not television station employees but were contracted to upgrade a transmission antenna, WPLG reported.

It is unclear what caused the collapse or how high up the workers were when the scaffolding collapsed.

The tower was completed in 2009, according to WPLG.