Local officials in Florida have approved the release of 750 million mosquitoes that have been genetically modified to reduce local populations.

The aim is to reduce the number of mosquitoes that carry diseases like dengue or the Zika virus.

The green-lighting of a pilot project after years of debate drew a swift outcry from environmental groups, who warned of unintended consequences.

One group condemned the plan as a public “Jurassic Park experiment”.

Activists warn of possible damage to ecosystems, and the potential creation of hybrid, insecticide-resistant mosquitoes.

But the company involved says there will be no adverse risk to humans or the environment, and points to a slate of government-backed studies.