Zia, 72, may face up to life in prison if found guilty on Thursday on charges of embezzling $252,000.
Her Bangladesh Nationalist Party (BNP) says police and other security forces have detained more than a thousand of its activists and officials in a nationwide crackdown before the verdict.
Dhaka Metropolitan Police said it feared opposition parties could “create anarchy” if she was convicted.
Her party says the charges against the two-time prime minister are politically motivated.
“I hereby declare that no processions- by standing up or sitting down- will be allowed on the roads that block public or vehicular movements,” Dhaka police chief Asaduzzaman Mia said in a statement.
BNP spokesman Ruhul Kabir Rizvi said police were raiding homes…