A 16-year-old boy has been arrested after two people were stabbed and a third was robbed at knifepoint.
All three incidents, in the Deepdale area of Preston on Sunday, are being linked, Lancashire Police said.
A man in his 50s was stabbed in the abdomen by a stranger at Sainsbury’s at about 15:45 GMT, the force said.
A woman in her 20s was stabbed about three hours later and shortly after a teenage boy had his bicycle stolen at knifepoint in a retail park.
The man underwent surgery for his injuries, which police said were not life-threatening.
The woman, who was attacked in Blackpool Road, was also transferred to hospital where she was treated for a single stab wound. Officers could not say if she had anything stolen from her.
‘Small geographic area’
Police arrested the 16-year-old, who is from Preston, on Sunday evening on suspicion of attempted robbery, robbery and wounding.
He remains in police custody.
Lancashire Police increased patrols in the vicinity and placed a Section 60 order, allowing officers to search people or vehicles, in the area until 03:00 GMT on Monday.
Insp Phil Orme of Preston Police, said: “These are very serious incidents where violence or threats of violence have been used.
“The incidents have been confined to a small geographic area and have been very similar in nature. At this stage, we believe they are linked.
“While we have made an arrest, our enquiries are very much ongoing. If you witnessed any of these crimes taking place or have any information at all that could help, please get in touch as soon possible.”