Hillsborough investigators are examining hundreds of pocket note books belonging to police officers.
The Independent Police Complaints Commission is looking at the books to see whether they contain anything relating to the 1989 disaster and subsequent inquests and inquiries.
As at the end of September, 112 notebooks had been handed in by serving and former officers who were on duty on the day of the disaster at Sheffield Wednesday’s Hillsborough stadium.
However, more have since been found in South Yorkshire Police buildings.
Deborah Glass, IPCC deputy chairman, said: “We are assessing the contents to identify any which date prior to 1992 – the time period covering the disaster and subsequent inquiries and inquests.
“We have found several hundred which fall within this period. These will now go through a further assessment process by the IPCC to see whether they contain any information of relevance to the investigation.”
The IPCC is looking into possible police misconduct in the disaster’s aftermath after it emerged police statements were altered to try to shift blame for the disaster from the police on to fans.
Some 96 Liverpool football fans were crushed to death in the tragedy.