Bangladesh lifted a ban on Facebook after it was imposed for security reasons few days ago.
The government banned Facebook, WhatsApp and Viber blocked last month after two opposition leaders lost their appeals against the death penalty for war crimes committed during the 1971 independence conflict.
The pair were hanged days later, hiking fears of opposition unrest in a country already reeling from deadly attacks by suspected Islamist militants.
Mobile messaging apps remained barred in the country. Bangladesh temporarily barred messaging services Tango and Viber in January after they became a popular way of mobilising large numbers of activists for anti-government protests.
A court last month rejected appeals by Salahuddin Quader Chowdhury and Ali Ahsan Mujahid, who were found guilty of atrocities carried out during the war with Pakistan.
Similar convictions in 2013 triggered the country’s deadliest violence since independence, with some 500 people killed – mainly in clashes between opposition activists and police.