Protestors were seen outside a Southampton church smoke grenades - alarming passers-by.

The masked campaigners held a banner showing 'Watch Christspiracy' while waving the devices which poured smoke outside St Boniface Catholic Church on Shirley High Street.

John Kingston, 40, was passing by when he saw the early morning incident today.

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He told the Echo: "I was going to Sainsbury's when I saw them. I must have been around 7am.

"They were shouting something but I just drove past. It was something to do with religion and the church and they were wearing masks and had smoke grenades.

"There is a bus stop near the church and there were a few people waiting for the bus and they said they were going to call the police.

"It was just an odd thing, they had their masks and were shouting."

Chirstspiracy is a documentary made by the same filmmakers behind Seaspiracy, a documentary which exposes the fishing industry's impact on the world's oceans.

According to Rotten Tomatoes, a film review website, Christspiracy, is about 'two daring filmmakers' who 'embark on a global quest sparked by the not-so-simple question 'Is there a spiritual way to kill an animal?' and along the way discover the biggest coverup in the last 2000 years'.

The description goes on to say: "For five years filmmakers Kip Andersen and Kameron Waters travelled around the world hopping from Rome to Jerusalem, Oxford to India - interviewing everyone from renowned theologians and archaeologists to Christian farmers and Indigenous shamans - all to reveal a massive coverup, one that will transform history forever.

"From the co-creator of the hit Netflix documentaries Seaspiracy, Cowspiracy and What the Health, Christspiracy is a fascinating investigation that will change the way you think about faith, ethics and our relationship with creation."

The documentary will be available in cinemas from March 20.

Hampshire police confirmed they had not been notified about this incident.