Protests against the Agnipath' scheme of recruitment in armed forces grew more virulent on Friday in Bihar, where a mob attacked the house of Deputy Chief Minister Renu Devi, besides causing heavy damage to railway property and affecting normal life in a number of districts.

The state has been witnessing agitations since Wednesday, a day after the government came out with the new scheme on a four-year contractual basis after which only 25 per cent shall be regularised based on performance assessment by seniors, while the rest will be discharged from service without pensionary benefits.

The large-scale violence and arson is a handiwork of goons instigated by the opposition parties. What else explains targeted attacks on BJP leaders? My house in Bettiah town was attacked. Window panes and a car parked inside got damaged. Thankfully, none of those inside was injured. Petrol pump owned by a brother of Sanjay Jaiswal (state party president) has also been vandalised, Renu Devi told PTI.

The deputy CM rued that she was planning to leave for Bettiah by helicopter to attend a number of functions, but had to put off the visit in view of the law and order situation.

In Motihari, adjoining Bettiah, the car of BJP MLA Vinay Bihari was pelted with stones and while the legislator and his driver were not injured, the vehicle was badly damaged.

The attack on BJP leaders comes a day after the party's MLA Aruna Devi was injured in a stone-pelting incident at Nawada, where the party office was also torched by the rampaging mob.

The police in Katihar district, taking a cue from Renu Devi's experience, has tightened the security around the house of Tarkishor Prasad, the other deputy CM who also happens to be the local BJP MLA.

The state capital, which had so far been largely untouched by the stir, witnessed some commotion as controversial former MP Rajesh Ranjan alias Pappu Yadav staged a demonstration on the Dak Bungalow crossing along with hundreds of supporters, causing huge traffic snarls.

Barely a couple of kilometres away, students staged a huge demonstration at the Kargil chowk and marched through Ashok Rajpath, flanked on either side by colleges affiliated to the Patna University and book shops, coaching centres and residential complexes doubling up as cheap hostels.

It is natural for the youngsters to be outraged at the Agnipath' scheme. They do not join the armed forces, putting their lives at risk, to be kicked out after four years with no pensionary benefits, Yadav told reporters.

He also scoffed at the rationale being given for the scheme that it will cut down the defence pension bill, saying such talk does not hold water in a country where you become eligible for lifelong pension upon becoming an MP or an MLA even for one day .

The young protesters demonstrating in front of Patna University were even more vocal.

They also said if the government thought reducing pension bills in this manner was fair, "it should do away with pensions of MPs and MLAs and shorten their tenure to two years".

It was, however, the railways that continued to bear the brunt of the protesters. The East Central Railway zone headquartered at Hajipur, which had announced restoration of normal rail traffic from 3.30 pm on Thursday, again came out with a list of trains that had to be cancelled, short terminated or diverted.

The mob set fire to 30 coaches of two trains, one each at Lakhisarai and Samastipur stations and torched a railway engine in Bettiah. A toll plaza in Deedarganj, the outskirts of Patna, and a police jeep in Nawada were also set ablaze.

Till Thursday evening, the state police had confirmed the arrest of 125 people, lodging of 24 cases and injuries sustained by 16 personnel.