Authorities concerned have intensified security vigil for all airports and 68 jails across the country following today`s suspected suicide blast at Ashkona barrack of Rapid Action Battalion (RAB) in capital."Instructions have been issued to intensify the security of our prisons . . . an extra security vigilance around the jails has been ensured to avert any untoward incident in and around the prison complexes across the country," Inspector General (IG) of Prisons Brigadier General Syed Iftekhar Uddin told journalists this afternoon.Referring to the intensified security alert following the incident at Ashkona`s proposed RAB office where a suicide bomber was killed, he said jail guards have been advised to wear vests on duty and rigorously screen inmates before taking them into prisons.The jail forces have also been asked strict surveillance surrounding jail areas with taking necessary measures if they encounter any suspicious activities, the prison chief said.Meanwhile, the law enforcers have beefed up security at Hazrat Shahjalal (R) International Airport and other airports throughout the country, apprehending subversive activities.Talking to BSS, Assistant Superintendent of Airport Armed Police (AAP) Tareq Ahmed (Media) said, "Security measures have been tightened in and around the Hazrat Shahjalal Airport . . . as part of the intensified security measures, the authorities have also restricted entry of visitors today."He added: "Based on intelligence report, the security at the airport has been intensified since 2 pm and it will continue until further instruction."Source: BSS