Ian Tomlinson lived and worked in the City of London
The police watchdog has said its chairman was wrong to say there was no CCTV footage of an alleged police assault at the G20 protests.
Ian Tomlinson, 47, suffered a heart attack and died during the demonstrations on 1 April.
Witness footage apparently showed Mr Tomlinson was pushed over by a police officer shortly before his death.
Independent Police Complaints Commission chairman Nick Hardwick had said CCTV cameras were not in the area.
On Thursday, a day after the commission took over the inquiry, Mr Hardwick told Channel Four News there was no CCTV footage because there were no cameras in the location.
However, the Independent Police Complaints Commission (IPCC) has now said that although Mr Hardwick believed he was correct at the time, it now appeared there were cameras in the surrounding area.
"From the outset it has been a main line of our inquiry to recover all CCTV from the Corporation of London and from all private premises in the area," said an IPCC spokesman.
"This work is ongoing and involves many hours of viewing and detailed analysis."
The police officer filmed in the footage has been suspended after coming forward.
Investigators are currently viewing all CCTV images from the City of London and private premises nearby, the watchdog said.
It also renewed its appeal for more information from the public, including video footage.
The IPCC has also ordered a second post-mortem examination as parts of its inquiry into the incident.