The investigation into the murder of Detective Garda Adrian Donohoe led to "thousands" of call data record requests as well as CCTV from 380 different locations being recovered, a court has heard.
The jury in the capital murder trial, which heard evidence yesterday for the first time in two months, was also shown charts of phone and text communications between the accused and two other suspects in the days leading up to the fatal shooting.
Aaron Brady (29), of New Road, Crossmaglen, Co Armagh, denies the capital murder of Adrian Donohoe (41), who was then a member of An Garda Siochana acting in the course of his duty, at Lordship Credit Union, Bellurgan, Co Louth, on January 25, 2013.
Mr Brady has also pleaded not guilty to the robbery of around €7,000 in cash and assorted cheques from Pat Bellew at the same location on the same date.
Evidence was yesterday given at the Central Criminal Court of telephone communications between the accused and a number of other people in the days before the murder of Det Gda Donohoe.
Edward McGoey, a senior intelligence analyst with An Garda Siochana, told the jury he prepared charts of phone contacts from mobile numbers of interest to the investigation team.
He said his involvement in this investigation was "much larger" than previous inquiries he had been part of, with the number of applications for call data records "in the thousands".
Detective Garda Gareth Kenna told the court that CCTV footage was obtained from around 380 locations during the course of the investigation.
Both witnesses were giving evidence simultaneously.
The jury was then shown footage of a dark saloon vehicle at a number of different locations between Ballymascanlon and Bellurgan on the night of January 22, 2013.
This vehicle was seen on footage at a service station, as well as being driven to and from the home of one of the robbery suspects' parents.
Footage was also played of a separate suspect buying mobile phone credit in a store.
Both men are alleged by the prosecution to have been involved in the robbery at Lordship Credit Union, but cannot be named for legal reasons.
Mobile phone traffic between Mr Brady, these two suspects and others was also shown to the court.
The trial continues before a jury of six men and seven women.
Earlier, Justice Michael White said measures had been introduced by the court in line with government guidelines on the pandemic and that the trial could continue.
The number of people allowed into the courtroom has been restricted, with some members of the jury sitting in the body of the court.
"If any of you have any on- going concerns about your health which impact on your ability to continue as a juror, please bring it to my attention," Mr Justice White told them.
The court heard one juror had requested not to continue because of concerns for his health as a result of the current pandemic.
He had been discharged, and the trial continues with a 13-person panel.
Mr Justice White also informed the jury that the court service had arranged to refund any parking costs that they may incur.