By yesterday evening, the army and navy were guarding Eastern Oil Refinery at Patenga in Chittagong, Daulatpur Oil Depot in Khulna, Ashuganj Gas Metering Station and Demra City-gate Gas Station. Deployment of the troops began on Tuesday.

Two platoons of the navy were dispatched to Eastern refinery, as many platoons of army to Daulatpur depot, one platoon of troops to Ashuganj and as many to Demra, said Lt Col Nazrul Islam, director of Inter-Services Public Relations.

"The forces were deployed after request from the energy and mineral resources ministry," he told The Daily Star, without mentioning a reason.

"They (army and navy personnel) were tasked with ensuring overall security of the installations in coordination with the installation authorities."

Official sources said the government took the measure in view of subversion concerns reported by intelligence agencies and security measures of the installations.

Earlier our Chittagong Corres-pondent said: Security of the prime port city of Chittagong was beefed up deploying the army and navy at all key point installations in fear of subversive activists.

Official sources said navy personnel were guarding Eastern refinery, country's lone oil refinery, oil companies and Patenga-based terminals overlooking the Karna-phuli river.

Bangladesh Petroleum Corporation (BPC) Chairman AKM Zafarullah Khan also confirmed stepped up security at all major establishments under his organisation.

"We have taken all precautionary measures to protect our KPI as instructed by the energy and mineral resources ministry. Any subversive activities in our installations may bring the entire country to its knees."

An oil terminal official at Patenga said: "We have also ramped up internal security after we received written instructions from the ministry. Our security staff here have been put on high alert and we have mounted watch on outsiders."

A round-the-clock watch was put in place at Chittagong port that handles 80 percent of cargoes with the calling of 1,500 vessels a year, officials said.

A team of 350 army men guarded Chittagong port jetties along with 600 security staff of the port authorities and 200 ansars.

Acting chairman of the port Abul Kasem said, "We have alerted our security men to step up vigil in and around the restricted areas in the aftermath of the arms and ammunition seizure."

Commissioner of Chittagong Metropolitan Police SM Sabbir Ali said police were also on the alert for subversive activities.

Police and coastguard seized 10 truckloads of rockets, rocket launchers, submachine guns, grenades, AK-47 riles on the Karnaphuli coast, sending waves of horror across the country.