Several bombs exploded in Bangladesh’s capital and police clashed with protesters Tuesday as opposition leaders enforced a daylong, nationwide general strike over police intimidation.

Witnesses and news reports said several homemade bombs exploded during the beginning of the shutdown. RTV and Bangla Vision stations reported explosions in parts of Dhaka. It was not clear if there were any injuries.Clashes were reported inside and outside Dhaka, and thousands of security officials were deployed in the capital to maintain order.Nearly 400 members of paramilitary Bangladesh Border Guard were also deployed to aid police in Dhaka, said Maj. Gen. Aziz Ahmed, the force’s director general.

Schools and most businesses in Dhaka remained closed Tuesday. Traffic was thin on the usually clogged streets.An 18-party opposition alliance led by the Bangladesh Nationalist Party, or BNP, was enforcing the strike to protest alleged police intimidation during a rally on Monday.

The party and its allies are demanding restoration of a caretaker government system to oversee upcoming elections. Its ally Jamaat-i-Islami also wants a halt to trials of several opposition politicians accused of crimes stemming from the country’s 1971 independence war.

After Monday’s rally, police arrested some senior leaders and more than 100 activists of the BNP, headed by former Prime Minister Khaleda Zia, in Dhaka during a raid on its party headquarters. Police said they also recovered at least 10 homemade bombs from the headquarters. But the party blamed police for keeping those bombs inside the headquarters to create a drama.

BNP’s acting secretary general, Mirza Fakhrul Islam Alamgir, and a former mayor of Dhaka City Corporation were among those arrested.Zia, in a late-night meeting with senior party leaders, criticised the government for the arrests and later announced similar nationwide shutdown for March 18 and 19 if the detained senior leaders are not freed immediately.

Zia’s party and Jamaat-i-Islami have denounced the trials of several opposition politicians accused of mass killings and atrocities during Bangladesh’s 1971 independence war against Pakistan.Bangladesh says the war left three million people dead, 200,000 women raped and forced millions to flee to neighboring India.

Jamaat-i-Islami campaigned against the independence of Bangladesh, but denies committing any atrocities.The administration of Prime Minister Sheikh Hasina initiated the trials in 2010 and three verdicts have already been declared. Ten of the defendants are from Jamaat-i-Islami, the country’s largest Islamic party, while the other two belong to the BNP.

Two of the senior party members of Jamaat-i-Islami have been convicted, one sentenced to death and another to life in prison. Another former member of the Islamic party has been sentenced to death. The sentencing sparked violent clashes between opposition activists and police, leaving about 70 people dead in recent months.