Patna, Jun 18 (IANS): Nearly half-a-dozen people were injured here in a clash, several trains were stopped and roads were blocked Tuesday when the BJP began a state-wide shutdown to protest what it called a betrayal by the JD-U.

Several trains were forcibly halted and national highway blocked Tuesday as the workers and leaders of the Bharatiya Janat Party (BJP) began a state-wide shutdown to protest the betrayal of ruling party Janata Dal-United (JD-U) that ended its 17-year-old alliance Sunday.

The cracks between the BJP and JD-U appeared when Bihar Chief Minister Nitish Kumar opposed Gujarat Chief Minister Narendra Modi and the BJP's decision to make Modi its public face for the 2014 Lok Sabha elections.

An angry BJP is observing Tuesday as 'Vishwasghat Diwas' in the state.

Nearly half a dozen workers of BJP and JD-U workers were injured after they clashed and attacked each other with bamboo sticks and iron rods in Patna during the shutdown.

According to police officials here, JD-U spokesperson Rajeev Ranjan and three other party leaders were injured when BJP workers attacked them following the clash.

The clashes took place after the BJP workers raised slogan against Chief Minister Nitish Kumar and JD-U workers countered them by raising slogan against Gujarat Chief Minister Narendra Modi, a police official said.

The BJP workers stopped half a dozen trains, including long route trains, at different railway stations across the state.

"Several trains were halted...," a police officer told IANS.

Roads, including the national highway, were blocked at various places across the state.

"The strike supporters, mostly BJP workers, blocked important roads including the national highway and state highway at various place," said a police official.

Authorities have "made elaborate security arrangements in view of the shutdown", assured a senior government official.

In Patna, shutdown evoked mixed response with busy roads like Ashok Rajpath, Bailey Road, Patna-Danapur Road and Fraser Road being blocked.

"Shops and markets were also closed in some areas".

Soon after the JD-U ended its alliance with the BJP, it was declared as a black day by BJP that accused JD(U) of `vishwasghat' (treachery).

The JD-U has 118 seats in the 243-member assembly, four short of a majority, while the BJP has 91 members. There are six independents, while the Congress has four members.