DHAKA, Bangladesh

At least 91 people, including 14 police officers, were killed and hundreds more injured by bullets across Bangladesh on Sunday as members of the ruling party and the police clashed with demonstrators calling for Prime Minister Sheikh Hasina's resignation.

As the situation worsened, the government extended the curfew indefinitely.

According to a statement issued by the Bangladesh Police Headquarters in Dhaka, 13 police officers were killed in "terrorist" attacks at a police station in northwestern Sirajganj city and one in eastern Comilla city.

Over 300 policemen have also been injured in protesters’ attacks at various police stations across the country, the statement added.

At least 77 people were killed in 18 districts of the country, including four in the capital Dhaka, daily Prothom Alo said, citing police and hospital sources. Those killed include protesters, the ruling Awami League and opposition Bangladesh Nationalist Party members.

Meanwhile, hundreds of people, including those who received bullet wounds, were admitted to different hospitals, it added.

The Prime Minister's Office in a statement referred to the violent protesters as terrorists.

Prime Minister Hasina has warned that her administration will take harsh measures against "criminals" who cause trouble.

In this emerging situation, the government ordered a shutoff of mobile internet, with Facebook and WhatsApp blocked again, the newspaper also said.

Earlier, the government had resumed mobile services after 10 days of blackout on July 28.

Meanwhile, the government has announced a three-day public holiday, starting from Monday.

The government has also increased patrolling to increase security during the ongoing curfew and extended it for an indefinite period amid the violent situation, according to a Home Ministry notification on Sunday.

Earlier, Bangladesh imposed a curfew on July 20 amid the first round of the student protest that had gone out of control since July 16.

Meanwhile, retired military officers on Sunday at a news conference in Dhaka urged the country’s armed forces not to face the students-civilians, besides taking initiatives to resolve the ongoing political crisis of the country through dialogue.

Former chief of Bangladesh Army Iqbal Karim Bhuiyan in a written statement on behalf of retired officers urged for a UN-run investigation against all the organized killings during the student protests.

Key coordinator Nahid Islam on Saturday at a massive rally in the capital Dhaka announced a non-cooperation movement. He called on Hasina to resign and take responsibility for deaths during the student protests.

The non-cooperation movement called on the public to refrain from all routine government activities, including paying taxes and utility bills, to shut down all factories and offices, and to shut down transportation until the Hasina government resigns.

Hasina on Saturday said justice would be done for those killed during student protests and also called for dialogue to end the protests. Protesters, however, rejected the call for negotiations.

Sunday has been tense across the country, as the ruling Awami League party mobilized its supporters to respond to the protesters.

Opposition BNP Secretary General Mirza Fakhrul Islam Alamgir on Sunday also called on supporters to help the students on the streets.

Over the past three weeks, the South Asian nation of 170 million people has been rocked by turmoil due to a student-led protest demanding reforms to government job quotas.

The government said at least 150 people were killed in the recent violence during the student protests in July. Local media, however, said over 266 people, mostly students, were killed with bullet wounds in clashes with police and members of the ruling party.