The Bangladesh Supreme Court on Monday upheld a death sentence by rejecting a review appeal of a senior Jamaat-e-Islami party leader convicted of committing war crimes in 1971.
After the decision, the party called a 48-hour nationwide strike from Tuesday leading to tighter security measures.
On Monday, one man died after violence broke out in Noakhlai district as police clashed with Jamaat activists.
A four-member panel of the appellate division of the court took the decision against Mohammad Qamaruzzaman, 62, an assistant secretary general of the party.
He is known to be popular among young leaders of the Islamist party. The party is a key ally of the opposition Bangladesh Nationalist Party led by former prime minister Khaleda Zia.
Qamaruzzaman was held responsible for the killings of 120 people during the 1971 independence war against Pakistan as the leader of a militia group, Al Badr, in Mymensingh district.
The execution is expected to take place soon as it is unlikely that he would get presidential clemency.