At least 59 people have been killed in Bangladesh amid worsening clashes between police and anti-government protesters.

The unrest comes as student leaders have declared a campaign of civil disobedience to demand that Prime Minister Sheikh Hasina step down, the BBC reported. 

Thirteen police officers were killed when thousands of people attacked a police station in the district of Sirajganj, police said.

The student protest started with a demand to abolish quotas in civil service jobs last month, but have now turned into a wider anti-government movement.