Tensions are mounting in Bangladesh, after violence broke out at opposition rallies.

Clashes between the police and opposition protesters have continued since Saturday. They come ahead of general elections due in January.

Over the weekend, a nationwide strike by the opposition Bangladesh Nationalist Party, or BNP, developed into clashes with security forces in the capital Dhaka. Media outlets are reporting at least one police officer and one political activist were killed.

Over four dozen people, including several journalists, were injured.

The BNP is demanding the resignation of Prime Minister Sheikh Hasina, claiming that a fair and free election would be impossible under her administration. The government maintains the election will be held under the independent Election Commission.

Police detained BNP Secretary General Mirza Fakhrul Islam Alamgir in connection with Saturday's violence. The BNP is strongly criticizing the government for what it claims is a crackdown.

On Tuesday, two BNP supporters were killed and dozens injured in a clash that erupted some 110 kilometers north of Dhaka.

Opposition parties have also started a three-day transport blockade.

The United States and the United Nations are urging all sides to maintain restraint ahead of the elections.