Pest control: A worker cuts grass and sprays insecticide at Diamond Hill.

The Lands Department is stepping up anti-mosquito work amid the current mosquito breeding season, Director of Lands Patrick Lau says.

Speaking after an anti-mosquito operation at Diamond Hill today, Mr Lau said the department has launched an inspection exercise for all fenced-off Government sites to prevent breeding.

"Some 600 pieces of Government land will be inspected in the first phase, and contractors will be commissioned to cut overgrown grass, remove water containers and rubbish as well as spraying insecticide," he said.

Inspection of the remaining 400-plus Government sites will be conducted in the second stage.

The public can report problems involving Government sites, including mosquitoes, by telephoning 2231 3294, or informing the department via fax at 2868 4707.

Residents are urged not to cultivate on Government land, particularly on hill slopes, which often create mosquito problems.

Those who are convicted of illegal occupation of unleased land are liable to six months' imprisonment and a $10,000 fine, while illegal excavation on such land can bring six months' imprisonment and a $5,000 fine.