Six houses in Bessacarr, Doncaster, were found to be insecure by police officers who were patrolling the area as part of Operation A/Optimal.
In the same area, on Clayworth Drive, police arrested two men, who were allegedly trying door handles in search of ones left unlocked on Monday night.
Supt Eddie Murphy, of Doncaster police, said: “Now we’re enjoying some warmer weather, it’s more important to remember to lock your doors and windows. It is no coincidence that we made arrests in an area where we found insecure properties.
“Most burglars are opportunistic and will take advantage of insecure properties and where valuables can be seen. Please don’t give them the opportunity to steal from you.”
Seven thefts from cars were also reported around Doncaster on Monday, where valuables had been left on show.