Farmers blocked highways and held demonstrations in many rural areas in northern India on Friday to protest over a range of grievances that have also led tens of thousands to march toward the capital in tractors and wagons.

Farmers in the northern states of Haryana and Punjab held sit-ins near toll plazas on major highways in the strike, supported by some trade unions.

Authorities advised commuters to plan routes carefully to avoid blocked roads.

Tens of thousands of farmers began a protest march toward New Delhi earlier this week to demand guaranteed prices for their produce, but were stopped by the police about 125 miles away from the capital.

The farmers are camping on the border between Punjab and Haryana after being blocked by concrete and metal barricades. Police detained some protesters.

Authorities have also suspended mobile internet service in some areas of Haryana, blocked social media accounts of some protest leaders and used drones to drop tear gas canisters on the protesters.

The farmers’ march comes two years after Prime Minister Narendra Modi’s government faced similar protests that continued for more than a year.

At that time, farmers camped on the capital’s outskirts to demonstrate against new agriculture laws that were later withdrawn.

At the heart of the latest protests is a demand for legislation that would guarantee minimum support prices for all farm produce.

Currently, the government protects agricultural producers against any sharp fall in farm prices by setting a minimum purchase price for certain essential crops, a system that was introduced in the 1960s to help shore up food reserves and prevent shortages.

The farmers want legislation that will apply the protection to all produce.

The protesting farmers are mostly from Punjab and Haryana and are relatively better-off than farmers in other Indian states.

But increasing cultivation costs and rising debts have led them to overproduce rice and wheat, crops for which they get a minimum support price, or MSP.

However, those water-guzzling crops have also depleted the water table in the two states and forced farmers to look for alternatives.

Farmers say a guaranteed minimum support price for other crops would stabilise their incomes.

Farmers are also pressing the government to follow through on promises to double their income, waive their loans and withdraw legal cases brought against them during the earlier 2021 protests.

Some economists say that implementation of the demands could risk food inflation.

However, experts also point out that a key cause of the farmers’ frustration is the lack of implementation of policies that are already in place.

Several meetings between farm leaders and government ministers have failed to end the deadlock.

Agriculture Minister Arjun Munda, who met farm leaders on Thursday, said the talks were positive and the two sides will meet again on Sunday.