This is the dramatic moment a billboard across a busy road was blown over during a sudden storm - landing on a tuktuk.

The huge metal structure was displaying a metal sign urging locals to 'Keep Cambodia Safe' when the powerful tropical gusts struck capital Phnom Penh on Friday evening at around 5:30pm.

Footage shows how the pounding rain downpour gathered pace - first toppling a cage of geese and then forcing motorcycle riders to stop.

Seconds later the metal sign came crashing down and landed on a tuktuk driver. He emerged from the wreckage and was treated for his injuries following the incident in the Phum Trapeang Chhuk district of the city during rush hour.

Shocked onlooker Ny Samut said: 'The wind was so strong. It came unexpectedly and made the buildings shake. It is scary when the storms happen.'

Traffic continued passing by the collapsed billboard before officials arrived later in the evening to clear the debris. The road was also flooded briefly due to the rain.

Cambodia and other countries in Southeast Asia such as Thailand, Malaysia, Indonesia and the Philippines are at the start of their tropical monsoon rainy season, which last until November.

Soaring temperatures reaching 35 degrees Celsius are often followed by powerful tropical storms with thunder, lightning, rain and flash floods which cause rivers to flow faster and become dangerous.

Many of the under-developed nations struggle to cope with the heavy rain due to under-investment infrastructure.

Cambodia, in particular, has suffered from decades of chronic under-investment and corruption following the rule of the genocidal left-wing Khmer Rouge party, which abolished money and executed up to three million people - wiping out the country's middle class in an attempt to create a agrarian society.