A teenage boy has been arrested after a pair of robberies in which a man was shot in the face and a 13-year-old was threatened with a hammer.
Norfolk police arrested a teenager on Sunday in connection with the Norwich robberies, which happened on Thursday last week.
The boy was arrested on suspicion of robbery and public order offences.
He has been released under investigation while inquiries continue.
Detectives had appealed for witnesses after the robberies, with officers concerned about the "serious nature" of the attacks over the half-term holiday.
The first robbery happened at the skate park at Hellesdon Community Centre in Woodview Road at about 12pm.
A 13-year-old boy was robbed of his bicycle by a teenager who was armed with a hammer.
The victim was threatened, but not injured.
However, the victim was hurt in the second robbery, which was described by police as "a nasty assault".
Two teenagers approached an 18-year-old man at the BMX track in Sloughbottom Park in Mile Cross at about 5.30pm and stole his bicycle.
As the victim was giving chase, one of the teenagers pulled out an air gun and fired it at the victim.
It left the victim with an air gun pellet wound just above his eye and he needed treatment at the Norfolk and Norwich University.
In that robbery, the teenager was also carrying a hammer.
The pair then fled the scene down Sweet Briar Road, heading towards the city and turning right at the roundabout with Dereham Road.
Police had linked the two attacks and had been scouring CCTV as part of their investigation.
They had also appealed for witnesses and for drivers, who had been travelling in the Sweet Briar Road area who had dashcam footage, to get in touch.
Anyone with information should contact Norwich CID on 101, or call Crimestoppers anonymously on 0800 555111.
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