TWO robbers mugged four people at knifepoint in just two hours.

In two of the incidents - which happened on the same road - groups of schoolboys were targeted outside St. Wilfrid’s High School in Blackburn.

The robbers, who brandished a lock knife, stole a total of £3 and a blazer from the children, before taking a BlackBerry phone and £30 from two older teenagers.

All the incidents happened as the pair walked out of Blackburn town centre along King Street to Whalley Banks and then Bank Top.

Detective Sergeant Mark Haworth-Oates said: “The level of forceful threat was completely disproportionate to the amount of money and property stolen.

"The victims are uninjured, but really shaken up."

At 3.40pm on Monday a group of five schoolboys from St Wilfrid's High School were confronted by two men in Whalley Banks.

One produced a knife and demanded cash. They took £1.50 before the group of friends ran off.

Five minutes later, three more St Wilfrid's pupils aged 15 and 16 were threatened by two men matching the same descriptions.

Again a knife was brandished and the men demanded cash.

They took one boy's blazer to search for items and made off with £1.

At 3.55pm the men struck again, having walked further along Bank Top away from the town centre towards its junction with Stansfeld Street.

A 19-year-old who had just been to meet his girlfriend from St Wilfrid's was threatened with a knife and had £30 stolen.

The couple were also warned not to contact police.

There was a gap then until 5.10pm when a 19-year-old man walking home from work along the junction with Hancock Street was stopped by two men who again threatened him with a knife and demanded money or mobile phones.

His BlackBerry was taken.

Police later swooped on a house in Hancock Street and arrested two men aged 21 and 22, and a woman aged 17, all from Blackburn, on suspicion of robbery.

They were being questioned by detectives last night.

St Wilfrid's headteacher David Whyte said the pupils involved had been offered support.

He said: “We have kept their parents fully informed and will help them if they need to go to court to give evidence.

"This sort of thing can happen anywhere. It wasn't a back street, but a main road in Blackburn town centre.

"It's a concern for all of us that this sort of behaviour can happen.

"The children carried on home and were responsible by immediately finding a police officer.

"Their quick actions helped prevent more people being threatened.

"We will be speaking to pupils in assembly and reminding them to be vigilant.”

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