South Wales Police says it is responding to "an incident" on Cowbridge Road East in Cardiff with armed officers.
Police were called out just before 4pm on Monday. Eyewitnesses say the officers went into the Lloyd's Bank.
A South Wales Police spokesperson told ITV News, "firearms officers were deployed to the area to ensure the safety of the public and officers at the scene."
A police helicopter was also seen circling the area.
The incident is ongoing.
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