Hertfordshire Police has said arrests have been made following a drive-by shooting which left a man critically injured.
The victim, who was in his 20s, was shot while riding an e-bike on the A41 in Watford on Thursday afternoon.
He was taken to hospital where his injuries were described as "life-threatening".
Road closures were put in place in both directions while investigations were carried out.
Det Ch Insp Katie Dounias, from the Bedfordshire, Cambridgeshire and Hertfordshire Major Crime Unit, said: “Arrests have been made in connection with [the] incident.
“We’d like to hear from anyone who was in the area and saw what happened or has dash cam footage.
"We are particularly keen to hear from anyone who witnessed the black BMW in the vicinity at the time of the incident."
Ch Insp Andy Wiseman added: “Following further intelligence which has come to light, we are now treating previous reports of targeted violence in Watford as connected.
“I understand news of this incident will be of concern to the community, and you can expect to see additional officers in the area as investigations are being carried out to determine the circumstances of what happened."
Aga Dychton, Watford Borough Council's portfolio holder for community, said: “We commend the extraordinary efforts of our police partners for making numerous arrests within 24 hours of the recent incidents in Watford.
"We want to reassure residents that this was a targeted incident, and there is no broader threat to public safety."
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