Two further arrests have been made in connection with the £50m Securitas robbery in Kent.
Two men told Mrs Dixon that her husband had been in an accident
Kent Police said two men, aged 55 and 33, were arrested in the Maidstone area on Saturday on suspicion of conspiracy to commit robbery.
Earlier, officers said they had pieced together the events leading up to the heist, including the kidnapping of the depot manager and his family.
The force also released a computer image of another raider.
The image of one of the two men who abducted Lynn Dixon and her son, Craig, shows a man wearing dark-style police clothing and possibly a wig and a false moustache.
He is described as white, skinny, 6ft to 6ft 2in, and in his mid to late 40s. He had a pasty complexion and a long thin nose, thin lips, a bony chin, thick, brown unkempt hair and a bushy dark brown moustache.
It follows the release of a computer-generated image on Friday of one of the men who kidnapped depot manager Colin Dixon.
On Saturday, police read out a statement from Mr Dixon describing the terror he and his family had gone through, and voicing his anger at the crime.
"The horror of what might have happened is with us in every waking moment," he said.
Kent Police said it was a reminder of the "callous" nature of the criminals involved.
Tests are still under way on several vehicles recovered since the raid.
Detectives said on Saturday they had worked out the route taken by the gang, as they drove the depot manager and his wife and son round the county before escaping with up to £50m.
'Rural farm building'
An appeal has gone out to commuters who may have seen the manager being stopped on the A249, or his family being moved between vehicles in Faversham.
The family's ordeal began when Mr Dixon, 51, left work at 1730 GMT last Tuesday to return to his Herne Bay home, but was pulled over 45 minutes later on the A249 by what he thought was an unmarked police vehicle.
He was handcuffed, put in a Volvo, moved into a van or a lorry some distance later, and taken to a rural building, thought to be a west Kent farm.
In Herne Bay, at 2000 GMT, his wife answered the door to two men posing as police officers who told her Mr Dixon had been in an accident.
They drove off with her and her son, now aged nine, in a waiting vehicle.
The armed gang forced the manager to let them into the depot
At Faversham, they were moved to a red van and taken to the farm.
There Mrs Dixon was able to talk briefly to her husband before she was moved to a Renault lorry.
Mr Dixon was put in a separate vehicle, Kent Police said.
All were taken to the Securitas depot in Vale Road, Tonbridge, at about 0130 GMT on Wednesday.
At the depot, 15 staff members were threatened, tied up, and kept in a room while the masked raiders loaded cash into the white Renault lorry.
In his latest appeal, Assistant Chief Constable Adrian Leppard said many motorists may have seen Mr Dixon being pulled over on the A249.
Police believe a burnt-out Volvo was among vehicles used by the robbers
He also said people may have seen Mrs Dixon and their son at the vehicle changeover in Faversham.
"Maybe someone in a rural area saw unusual activity nearby," he said.
He added: "Please think back, for however trivial something may seem to you, it could be an important piece in the jigsaw."
On Friday, a tip-off from a member of the public led to a white Transit van being found in Ashford with a large amount of money in it, thought to be from the raid.
Earlier, police revealed that several vehicles used in the raid had been found. The lorry is still missing.
Three people arrested during the investigation have been released on bail.