A clash ensued between police personnel and Madhesi Morcha cadres at Lahan in Siraha district on Saturday.

The clash erupted after the Morcha cadres tried to foil the CPN-UML’s party joining programme.

Meanwhile, police have arrested 18 persons including Sanghiya Samajbadi Forum Nepal district chairman Badal Yadav and leader Nabin Yadav from the scene. They have been kept at the Area Police Office, Lahan.

Earlier, the Morcha, an alliance of seven Madhes-based parties, cadres had tried to disrupt the UML’s Mechi-Mahakali campaign in various districts of Tarai.