The clashes have taken place between the security forces and the protestors at the bus park area.
Nepal police have fired three rounds of teargas shells to take the situation under control after the agitating cadres pelted stones at the security forces near the Shankaracharya Gate.
"Police resorted to opening three rounds of teargas shells to take the situation under control after United Democratic Madhesi Front (UDMF) cadres pelted stones at the security forces from the no man's zone", Chief District Officer of Prasa Keshav Raj Ghimire said, adding, " now the protestors have moved toward the Indian land.
Earlier, the protestors had pushed the security forces from Miteri Bridge back to the Shankara Gate. The demonstrators are still pelting stones at the Nepal police from the no man's zone, said Abhushan Timalsina.
The tension flared up as soon as around 500 Indian containers that had been stranded in Birgunj due to UDMF sit-in passed through the checkpoint. Police had arrested two Indian citizens in course of removing tents being used by the United Democratic Madhesi Front (UDMF) cadres at the Birgunj checkpoint on Monday morning.
A huge number of security forces have been mobilized at the Birgunj checkpoint after chasing away the cadres that had been staging protest since last 40 days.
The security force chased away the cadres from the checkpoint at 4:30 am today.