Gwent Police has said it will stamp out antisocial behaviour after increases in Bargoed and Blackwood.
In Bargoed, officers have promised a “zero tolerance” stance after an increase in underage drinking in the town.
Hotspot areas for teenaged drinking have included the recreation ground near the YMCA and under the viaduct in Commercial Street.
In the last four weeks more than 400 youths have been stopped and spoken.
In Blackwood, officers and Caerphilly County Borough Council have joined forces in tackling antisocial behaviour at the bus station.
High visibility patrols by the council’s Community Safety Wardens and local bobbies has seen more than 30 fines issued and four arrests made in recent weeks.
Neighbourhood Policing Inspector for Blackwood Mark Smith said: “The week of partnership working with the Police Officers, Community Support Officers, Council Community Safety Wardens and CCTV operators shows our commitment to jointly tackle this issue.
“The very successful week saw a reduction in crime and anti-social behaviour and it also reassures the public of our commitment to making this area a safer and a more user friendly environment. It is very much ‘work in progress’, with both high visibility and plain clothed police patrols continuing.”