Pakistani Muslims at a Karachi mosque clashed with baton-wielding police trying to enforce new curbs on gatherings to prevent Friday prayers and contain coronavirus infections, officials said.
TV footage showed dozens of people chasing two police vehicles and pelting them with stones as an officer fired in the air to disperse the crowd.
Health experts have warned an epidemic in South Asia, home to a fifth of the world's population, could easily overwhelm already weak public health systems in the region.
But Muslim-majority Pakistan and Bangladesh, and India, home to the world's largest Muslim minority, have struggled to persuade conservative religious groups to maintain social distancing.
After failing to persuade worshippers to pray at home last week, the government in Pakistan's southern province of Sindh, home to the financial hub of Karachi, enforced a lockdown for three hours beginning at noon on Friday, officials said.
"In the greater interest of saving lives, a decision to ban the prayer congregations at mosques has been taken," said Syed Nasir Hussain Shah, Sindh's minister for local bodies and information.
Pakistan has so far reported 2,458 coronavirus infections, fuelled by a jump in cases related to members of the Tablighi Jamaat, an orthodox Muslim proselytizing group.
