Security has been tightened at Katunayake Bandaranaike International Airport and Mattala Mahinda Rajapaksa International Airport.
This is due to an email received via the official BIA website, threatening an attack on the airport.
It further stated that BIA and other government institutions would be attacked on 20 September if the four persons named in the email are not released.
Reports say that it is suspected that this could be a Trojan attack to steal data, when access is granted to the website and the network when attempting to investigate the email.
Investigations so far have revealed that a website of a Bangladeshi armed forces institution has been hacked and the email sent through it.
Media reports say that based on this email, security in Mattala and Katunayake has been strengthened and drills were conducted to prepare for emergency situations on 14 September.
The number of police and Air Force have been increased in BIA, while roadblocks and searches are conducted by the army.
Reports say the heightened security will last till 20 September.
Mattala airport too will see 24-hour patrols, search operations, and road blocks.