What is the ruling on an employer who prevents his workers from attending Friday prayer, even threatening to dismiss them if they go, under the pretext of fear of spreading infectious disease, despite the fact that they go out daily for work and interact with people?

Attending Jumu'ah (Friday prayer) is an individual obligation (fardh 'ayn) upon every capable person. An employer is not permitted to prevent an employee from attending it, unless there is a fear for the property for which the employee was hired to guard. The employer should be reminded that he is not allowed to prevent Muslims from attending Jumu'ah, and that what he mentioned is not an excuse. One can seek assistance from the country's laws if they are beneficial. As for someone who is in need of work and cannot find any other, they have latitude in missing Jumu'ah and will be excused. However, whoever would not be harmed by leaving the job should leave it and seek other employment.