The Bihar police have apprehended four persons, including two from Jammu and Kashmir, on suspicion of maintaining links with a cross-border terror outfit.
The men were arrested near Basmatia village in Araria district near the India-Nepal border.
Police sources said the men, whose voter identity cards identified them as Siraj Ahmed Butt and Naseer Ahmed, hailed from Shopian district in Kashmir.
Their accomplice, Mohammed Shahabuddin, was now residing in Nepal's Sursani district, which forms part of the Kosi basin running along the porous India-Nepal border.
The fourth person, Virendra Mandal, who belongs to Supaul district, has been held for questioning on grounds that he was ferrying the men from Shopian during the past week.
“It was Mandal who ferried the duo to places such as Forbesganj in the district before dropping them at the Nepal border. They were nabbed along with Shahabuddin on their re-entry to India via the Bihar border at Araria,” Araria Superintendent of Police Shivdeep Lande told The Hindu.
He said that throughout his interrogation, Mandal denied knowing the identities of the two men, insisting that he was acting on his neighbour's instructions.
This fifth man was now under surveillance in Supaul, sources said.
The district police have been put on high alert since the intimation of a terror threat to blow up Raxaul and other railway stations along the Bihar-Nepal border earlier last month, with intelligence reports suggesting that a team of eight terrorists had sneaked into the State through the border.