The construction work on the bridge connecting Okhaldhunga, Solukhumbu and Khotang districts was scheduled to be completed within the current fiscal year.

"Our workers continued working till 8 pm. We were informed about the bridge collapse half an hour after our workers returned from the site," said a representative of the contractor, adding that they were yet to ascertain the reason for the collapse.

Waiba Construction Company had won the contract for the bridge construction. The southern end of the bridge bearing 225 tonnes of steel has collapsed. An estimated 700 tonnes of steel was used on the bridge which was being constructed in two parts.

Arjun Aryal, the chief of Harkapur-Okhaldhunga road project, informed that a team of technicians from the Capital were on their way to the site for investigation. "The reason behind the collapse can be determined only after a thorough investigation," said Aryal, adding that it may take 2-3 days to identify the probable cause.

Although the contract for the bridge construction was signed 12 years ago, the construction had been delayed for various reasons.