Burglaries are set to boom in the next few months, police warned today.

They increase at this time of year, mainly due to homeowners leaving doors and windows open in the warmer weather. Police in Brighton and Hove have launched a campaign to warn residents and beat opportunist thieves.

Posters showing a police footprint are going up round the city offering crime prevention advice and warning: "Take heed or the next boot print you see could be a burglar's."

There were 421 city break-ins last year between January and March, 523 in April to June and 573 between July and September.

A police spokeswoman said: "When it is hot outside, the natural thing to do is to keep windows and doors open, especially when just popping out for a short period of time.

"To the opportunist burglar it is almost an invitation as it makes it so easy for them to get inside the property.

"Once there, they are likely to steal things that are easy to sell such as televisions, videos, computers, jewellery and antiques. Being burgled can have a devastating effect and it is our job is to ensure as few people as possible go through it.

"If you hear something out of the ordinary, perhaps a glass pane being broken or a door being pushed, don't ignore it, call the police."

Brighton and Hove police offer the following advice:

Ensure your front door and all accessible windows are secure.

Fit a five-lever lock (to British Standard BS 3621) to your front and back doors with slide bolts both top and bottom. If you have an integral door for the garage, this should also have a five-lever mortice lock and slide bolts.

French windows and patio doors should be fitted with a security mortice bolt. Get specialist advice on fitting these locks.

Most opportunist criminals prefer to remain unseen so think of fitting
security lighting, either dusk to dawn low-level lighting or infra-red passive. You can also consider pea shingle on beds, gravel path and driveway and plants with sharp spikes under windows and down pipes.

Fit a bar chain or bar and, if you have a solid front door, a wide angle door viewer. Don't let anyone into your home you don't know. Check identification. Official visitors won't mind being asked for proof of identity. Be vigilant.

Empty boxes left outside advertise you have new goods inside, so dispose of packaging and boxes carefully.

Property mark your valuables by using your post code and your house number or name. Some articles are unsuitable for marking, so photograph them against a plain background.

Put your garden tools away in a secure garage or tool shed, as they
could be used to break into your home. Secure your garden shed with strong hinges, hasp and staple, good padlock and window locks.

Intruder alarms are an effective deterrent against burglars. Before choosing a system ensure it is the most suitable for your needs.

Join a Neighbourhood Watch Scheme. For details of a local scheme or to start a new one, phone 0845 6070999 and ask for the crime prevention co-ordinator in your area.