The Delhi Metro Rail Corporation on Wednesday issued a red alert for its entire network following advice from security agencies amid heightened tensions between India and Pakistan. The metro covers 327 km with 236 stations in Delhi and its vicinity.

“As advised by security agencies, a red alert has been imposed on the entire DMRC network from 6 pm onwards,” the corporation tweeted.

An unidentified official told the news agency that after the alert is issued station controllers are required to “inspect entire station premises for any suspicious items or activity”. The station controllers have to report to the control centre every two hours, the official added.

Reports of both India and Pakistan shooting down each other’s fighter jets emerged, a day after the Indian Air Force struck a terror camp across the Line of Control. Pakistan said on Wednesday that it has taken Indian Air Force official, Wing Commander Abhinandan, into custody.