Police have issued a warning after 120 motorcycle thefts in three months across Hertfordshire.

Watford and Hertsmere are among the areas to have been particularly targeted during the period, according to officers.

Police believe a large proportion were "opportunistic" thefts and most of the motorcycles were unsecured at the time.

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A crime prevention message issued to residents read: "Hertfordshire Constabulary is asking motorcyclists to make sure their bikes are secured following an increase in thefts in recent months.

"More than 120 motorcycles have been stolen in the last three months across the county, with most offences occurring in the Welwyn Hatfield, Watford, Hertsmere and St Albans areas."

A spokesperson for Hertfordshire Constabulary added: "We have been running crime prevention messages over the last month to help owners protect their bikes."

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Bike owners can help protect their vehicle in a number of ways including locking it, having the bike security marked with a vehicle identification number, and using a designated motorcycle parking place with a stand and security loop.