Flash floods washed away cars and injured dozens of residents in Indonesia.

Footage shows the deluge swamping streets in a neighbourhood in Mataram, in West Nusa Tenggara, on July 6.

The high floods washed debris and cars on the streets as locals fled to higher floors to escape the flood.

The Provincial Disaster Management Office (BPBD) said more than 30,000 people were affected by the floods in Mataram and surrounding areas.

Ahmadi, head of the West Nusa Tenggara BPBD, said: 'There are 15 injured victims and 520 displaced people. The number of fatalities and missing people is still being collected.'

He warned residents to remain vigilant as more rainfall accompanied by strong winds were expected to batter the region.

The Meteorology, Climatology, and Geophysics Agency (BMKG) reported that the 'rainwater spill' in Mataram reached 4.2 billion litres.

Indonesia and neighbouring countries in Southeast Asia are at the start of their annual monsoon rainy season which sees soaring temperatures followed by powerful rain storms. The rudimentary infrastructure often struggles with the deluge, leading to widespread flash floods.