A week on from the dramatic raid that seized Venezuela’s Nicolás Maduro, details of the intelligence surrounding the operation are becoming clearer, but some mysteries still remain.

The mission took months of planning and intelligence gathering. In August the CIA is believed to have sent a team of undercover officers into Venezuela.

The US does not have a functioning embassy in the country, so the team could not use diplomatic cover and were working in what is known in the intelligence worlds as a “denied area”. They were on the ground to scout targets and recruit people who could help.

US officials have said they had one particular source who was able to provide detailed intelligence on Maduro’s whereabouts which would have been critical to the operation.

Identities of such sources are normally highly protected but it quickly emerged it was a “government” source who must have been particularly close to Maduro and in his inner circle in order to know where he was going to be, and when.

That has led to intense speculation about who it was and what has happened to them. But their identity is still not public.

All of the human intelligence on the ground fed into a “mosaic” of intelligence to plan the operation in conjunction with technical intelligence like mapping and satellite imagery.

The scale, speed and success of the operation were unprecedented.

“This thing worked like clockwork. That doesn’t happen often,” explains David Fitzgerald, a former Latin America Chief of Operations for the CIA who also worked on planning missions with the US military.

“It is not the military tactics that drive the operation, but the intelligence.”

Around 150 aircraft were involved in the mission, with helicopters flying only a hundred or so feet above the terrain to get to Maduro’s compound.

There are still some mysteries though. One is exactly how the US turned off the lights in Caracas in order to enable the special forces to arrive.

“The lights of Caracas were largely turned off due to a certain expertise that we have – it was dark and it was deadly,” US President Donald Trump said.

The fact that the US Cyber Command was publicly thanked for its role in the operation has led to speculation that US military hackers got inside Venezuelan networks in advance to shut the grid down at the right moment – but details are limited.

The failure of Chinese and Russian air defences has also led to speculation of what kind of jamming or electronic warfare technology was deployed by the US in the air to aid the operation. The US Space Command, which operates satellites, also received credit for creating a “pathway” for the special forces to enter unseen.

Stealth drones were also thought to have been deployed. Exact details of the capabilities used are likely to remain secret, but America’s adversaries will be doing their best to try and understand what happened.

Those who have planned complex operations say it is remarkable that everything went according to plan, something that does not usually happen. One helicopter was hit but was still able to fly and no US forces were killed.

There are still few details about the battle that took place at Maduro’s compound, Fuerte Tiuna.

The Cuban government said that 32 of its nationals were killed by US forces. These were bodyguards provided to defend Maduro by its ally, Cuba. The Caribbean country provides not just bodyguards, but wider security support to the regime.

“Within the immediate perimeter of Maduro, there were probably zero Venezuelan security officers and on the outer perimeter maybe a mixture of both,” says Fitzgerald.

The fact that they proved so ineffective has also led to questions about whether some elements of the regime facilitated the mission in some way.

US forces were also able to get to Maduro as he was trying to lock himself into a steel safe room but before he could close the door.

They had blowtorches and explosives ready to blow the door open if needed, but the speed of the apprehension again suggests an incredibly detailed understanding of the layout of the compound.

The CIA undertook a classified assessment in advance of the operation, looking at what might happen if Maduro was removed.

The analysts examined a series of options and, according to reports, came to the view that working with elements of the existing regime offered more chance for stability than trying to install the opposition in exile in power. That helped solidify the view that the US should work with Delcy Rodríguez the vice-president.

There are thought to have been back-channel, secret contacts with elements of the Maduro regime in advance of the operation to discuss how people might position themselves given different potential outcomes.

The exact detail of those remain mysterious but they likely do much to explain why the mission took place, why it was successful and also what the plan is next.