A man went into a clinic and shot another dead with a gun hidden in a bag in front of terrified patients.
Horror CCTV footage shows how Isaías Vieira da Silva was murdered in the physiotherapy centre.
The smartly dressed suspect walks calmly into the reception area with a bag under his arm.
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Da Silva, 36, is seen seated using his mobile phone and does not seem to react when the gunman walks past.
He uses his mobile before placing it in his trouser pocket, as Da Silva gets up to leave, and follows him as he walks towards the exit.
He then pulls a gun from his bag, aims at Da Silva’s head, and fires.
Others in the waiting room, in Arapiraca, Brazil, flinch and run for cover as he drops dead to the floor on Monday (13 May).
Reports say the victim was found with a .32 calibre revolver with six bullets inside.
Three more bullets were allegedly found in the bag he was carrying when he was killed.
Da Silva worked in private security, as reported on Need to Know.
The police say that in April he was shot in the leg in a suspected murder attempt.
Three men pulled up in a car and opened fire at him.
He retaliated by shooting back, but his assailants fled.
He told police at the time that he was a licenced collector, shooter and hunter, which is why he was armed.
His gun was seized at the time.
He was receiving physiotherapy for his leg injury when he was killed.
According to witnesses, the perpetrator snapped a photo of his victim on the floor before fleeing the clinic on foot.
The authorities are investigating the case.
They believe the killing and the prior shooting may be connected.
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