Twelve people have died during a massive three-day traffic jam in Indonesia that stretched more than 20 kilometres and brought thousands of holiday-makers to a complete standstill, an official said on Friday. The horror traffic at a major highway junction at Brebes, a city on the main island of Java, was so bad that Indonesians dubbed the disastrous toll gate "Brexit", from the words "Brebes exit".

Roads across the world's most populous Muslim-majority country are choked every year at the end of the holy month of Ramadan, as millions head to villages to celebrate Eid, which fell on Wednesday.

But the chaos at the "Brexit" junction this year was particularly acute in the three days before Eid, as tens of thousands of cars crammed the arterial highway, transport ministry spokesman Hemi Pramuraharjo told AFP.

"In terms of this Brexit case, there's been a total of 12 victims over different days," he said.

The deaths occurred between July 3 and July 5, not a single day as earlier reported, he said.

Pramuraharjo said several of the victims were elderly while others died from fatigue and other health complications. Local media reported that a one-year-old suffering from fume poisoning was also among the deceased.