The daring heist was first reported in the Birmingham Mail, which claims that thieves used a stolen truck to knick the first load of parts in just six minutes, before returning for a second successful crack later the same night.
The local publication alleges that the crime took place in full view of security cameras, and say police are now hunting the gang behind the theft.
A JLR spokesman said: "We can confirm that we are working closely with West Midlands Police to investigate the theft of engines from the Solihull manufacturing plant.
"A reward is on offer to anyone who has information which leads to the successful recovery of these engines.”
Insiders told the Mail that the stolen 40-tonne truck arrived at the Solihull depot at 10.30pm on Tuesday and entered through a security-manned gate.
The truck then hooked up to a trailer containing the car engines, before driving out. Sources said the perpetrators obtained paperwork from the site before leaving — making their escape easier.
The stolen truck is then believed to have unloaded in the Coventry area, before remarkably returning to the factory a couple of hours later, hooking up another trailer, and driving off with more engines.
West Midlands Police said: “Police are appealing for any information in relation to a large scale theft of Jaguar Land Rover engines in Coventry.
“It is believed the engines were stolen from the Damson Lane site in Tile Hill sometime between late night Tuesday 31 January and the early hours of Wednesday 1 February.
“An articulated truck is believed to have entered the site twice, each time hooking up to trailers carrying the engines and then leaving again through the gate.
“The empty stolen trailers have since been located.”
The engines would have been waiting to go into vehicles being assembled. Solihull recently got a £1.5 billion investment. The new aluminium- intensive architecture body shop and final assembly cover an area equivalent to 22 football pitches.
It's not the first JLR-related theft in recent times. Two years ago, five Range Rover Sports destined for the new James Bond film Spectre were stolen from a Land Rover facility in northern Germany.
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