At Srirampur, the 'Dadagiri tax' averages at Rs500 per truck. Empty trucks are charged Rs 200.
It has been more than a years since the BJP-led coalition government took charge in Assam. Last week, on the government's anniversary Prime Minister Narendra Modi flew to the state and praised the administration for solving a large number of the problems.
But an NDTV investigation however has found that one of the government's first promises - stamping out illegal extortion rackets - was seemingly floundered on the state's highways.
To top it, truckers and collection agents involved in this illegal extortion syndicate claim that it's the Assam Police which not only "protects" them but a section of the top officials force are the kingpins behind this high state game.
Illegal and forceful tax collection at the border check gates was prevalent during the previous Congress regime as well. No less than Rs 6 crore is collected illegally in a month, though the very first decision of the Sonowal cabinet was for a crackdown against this racket.
In video recorded with hidden cameras, at the Assam-West Bengal border check gate at Srirampur, about 280 KM away from Guwahati, people are seen collecting money from truckers - an illegal and forceful extortion locally called the 'Dadagiri Tax' a practice for years together that Mr Sonowal wanted to end.
Every day hundreds of truck pass through the National Highway 31C - the main highway that links North East India to the rest of the country - and each one of them pay a very heavy illegal tax to ensure their safe passage.
"We have to pay for bordering passing and also the illegal collection, which is called Dadagiri Tax. We have to pay both times while getting into Assam and while leaving Assam. For few months the illegal collection was not happening, it has started once again," a truck driver said.
At Srirampur, the 'Dadagiri tax' averages at Rs500 per truck. Empty trucks are charged Rs 200.
Added to it is Rs 100 each needs to be given to sales tax personnel and motor vehicle inspector despite carrying all valid papers.
On an average, 1,200 truck pass in a day through Srirampur. The daily illegal collection is estimated to be Rs 9.6 lakh.
And there are special cases - trucks carrying poultry have to pay Rs 1,000, in a day.
In all, it is estimated the at least Rs 6 crores is illegally collected in this way under the racket a month.
Asked about the racket, Assam police chief Mukesh Sahay, "As for clandestine activities, there are black sheep ever where, but our mandate is clear that if we get proof that strict action will be taken."