Horrified onlookers didn’t know whether the incident was real or a joke.
Here’s everything you need to know about what happened.
What happened to the zoo worker?
The zoo contractor was filmed by visitors to the zoo approaching the big cat and putting his hand through the bars.
He is seen trying to pet it, clapping at it and touching its teeth.
The zoo worker wrestles with the lion who is biting his finger after he put it through the bars (Pic: @OneciaG/Twitter)
The lion growls as a warning, but he continues to pester him, until the big cat sinks its teeth into his finger.
The zoo contractor is seen screaming and trying to pull his hand away from the lion’s mouth.
He even puts his feet up to the bars to try and pry his fingers away.
Finally, he manages to free his hand, losing his right ring finger down to the joint, in the process.
The video depicts the moment when the finger is ripped off, with parts of the man’s finger seen being pulled by the lion’s mouth.
After the incident, the injured worker walked to a vehicle and is thought to have gone to hospital.
You can watch the video, which was shared on Twitter below, but please be aware it shows graphic injury and features swearing throughout.
Why did he put his hand through the bars?
There has been no comment from the man who has lost his finger, but Jamaica Zoo has issued a statement.
They said: “The actions displayed in a video by a contractor to Jamaica Zoo is tragic and do not represent the safety procedures and policies that must be adhered to at all times at Jamaica Zoo.
“We are currently reviewing the video, with a view of preventing any future recurrences.
“It is an unfortunate event that should never have happened, and we the family of Jamaica Zoo are doing everything to assist the gentleman in moving forward.
“We do hope you continue to support Jamaica Zoo. We have always been and will continue to be a safe place for you and your family to visit.”
The incident has caused concern about treatment of animals at the zoo, especially about what will happen to the lion involved.
The managing director of the Jamaica Society for the Prevention of Cruelty to Animals, Pamela Lawson will be visiting the zoo to see how this could have happened.
She said: “We will be going down there and I will be communicating with the National Environment and Planning Agency who has oversight over Jamaica Zoo.”
Onlookers, who were on a tour of the zoo were horrified to witness the incident, with many initially thinking it was a joke.
One witness, who didn’t give their name, told the Jamaica Observer: “When it happened, I thought it was a joke. I didn’t think it was serious. I didn’t realise the seriousness of it, because it’s their job to put on a show.”
They added: “Obviously, when he fell on the ground everybody realised that it was serious. Everybody started to panic. The entire skin and about the first joint of his finger was gone.”