An angry mob set fire to trains in India on Friday during protests against a new short-term military recruitment scheme that have erupted across the country.

Authorities are reeling from a sudden and violent backlash following the announcement this week of a plan to modernize India's 1.4 million-strong armed forces, which would deprive aspiring soldiers of benefits and job security.

Hundreds of protesters blocked passenger trains in Secunderabad's southern city, burning piles of debris and setting carriages on at least four trains on fire.

Officers fired live rounds to disperse the crowd, injuring at least one demonstrator, according to an AFP photographer on the scene. Telangana state police and officials could not be reached for comment.

Protests have erupted in several cities across the country since Thursday, with the eastern state of Bihar seeing the most violence.

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Crowds have set fire to more than a dozen trains and attacked the deputy chief minister's home, as well as offices of the ruling Bharatiya Janata Party (BJP). According to senior police officer Sanjay Singh, more than 100 people have been arrested across Bihar.

"Video recordings are being made of protests," he added. "Protesters will be identified and action will be taken against them."

To prevent the unrest from spreading, authorities imposed a curfew in Gurgaon, a satellite city of New Delhi, and temporarily closed some metro stations in the capital.

'A careless government'

The "Agnipath" (Path of Fire) scheme aims to enlist young adults in the armed forces for four years, which is a significant departure from the past, as enlistment is traditionally viewed as a path to a lifetime job.

Only a quarter of the new recruits will be offered permanent positions in the army at the end of the program, missing out on benefits such as pensions enjoyed by current personnel.

The recruitment plan was claimed by Prime Minister Narendra Modi's government to be aimed at modernizing India's armed forces with a younger and leaner soldier corps while also creating hundreds of thousands of new jobs.

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Following the start of the protests, the government announced that the upper age limit for Agnipath applicants would be raised to broaden eligibility and compensate for recruitment disruptions caused by the coronavirus pandemic.

"The relaxation of age indicates that the government cares for our youth," Defense Minister Rajnath Singh said Friday. 

Unemployment has long been a millstone around the neck of the Indian economy, with unemployment figures at their lowest since the 1970s, even before the Covid-19 pandemic wreaked havoc on local commerce.