Police say it was an 'isolated incident' which they dealt with at Tesco in Ramsey, with two suspects now in custody.
The store on Bowring Road was closed and the area cordoned off earlier this afternoon, Saturday, February 7.
Footage filmed by the public shows armed officers arresting a suspect on a public bus.
Officers went on to say the supermarket and its car park will stay closed at this time, 4.20pm.
Further updates will be released via the police's Facebook page.
Castletown police station could be yours... for £250,000
Fancy owning a landmark building in the south of the Island?
Brewery advertising for operator for landmark Laxey pub
Could you run one of Laxey's best-known pubs?
Hospice cafe reopens next week after refurb
A much-loved café will be throwing open its doors again next week.
Another one bites the gust - as Ramsey rocks cancelled
A huge live music event in Ramsey this weekend has been cancelled.
Mountain Road closed again after crash
The Mountain Road is currently closed after a crash.
Merchant Navy Day to be marked with memorial service
Merchant Navy Day will be marked on Island with a remembrance service for those who lost their lives at sea.
Fundraiser launched for injured MGP rider
A fundraiser's been launched to raise money for a Czech rider who was injured during the MGP.
Noel back in the saddle after handy pub pumping leaves him smiling
Noel Edmonds has thanked a pub in the north of the Island for helping out when he felt a little deflated.
