Six people have been arrested after a gang entered a sixth form college in Lancashire armed with knives, injuring a student and threatening others before fleeing.

The men came into Runshaw College in north-west England on Monday at 4pm. They attacked a 17-year-old boy who suffered minor injuries before running off when the police arrived.

Officers said the group of males are believed to be from Manchester. Three were found in a nearby car, while another was arrested on foot and a fifth stopped by police in a car. The sixth man was arrested on Monday evening.

Gary Crowe, chief inspector of Lancashire police said: “We believe this was a targeted attack in that we think the group have gone to find someone and a separate student has received a minor injury.”

He added: “I would like to reassure people that the incident has now come to a close. The safety of the college’s students and staff remains our priority and so we have stepped up patrols in the area and this will continue.”

The college tweeted to say the matter was being investigated but that it would be open on Tuesday. It called for anyone with information to get in touch with the police.

Lancashire police said they got a tip-off at 10.40am from a member of staff that a group was coming to the college from Manchester “with weapons”. Officers saw the gang come into the college grounds shortly before 4pm armed with knives and threatening students.

“When patrols arrived, the group made off from the college,” the force said. “Three people who were inside a parked Nissan Micra close-by were arrested. A fourth person who made off on foot was also arrested.”