BEIRUT, Lebanon — Saudi Arabia has begun a wide-ranging crackdown against perceived opponents of the policies of the kingdom’s new crown prince, Mohammed bin Salman.

Over the last week, 16 people were held, their friends, relatives and associates said in interviews. They include prominent Islamic clerics, academics, a poet, an economist, a journalist, the head of a youth organization, at least two women and one prince, a son of a former king.

Some of them were taken from their homes in unannounced raids by security forces, and their computers, cellphones and personal papers were seized, the friends and relatives said. Those arrested have been held incommunicado, and it is not clear if they have been formally charged with crimes. Saudi Arabia has not publicly released any evidence it might have against them.

Saudi activists have circulated lists of 30 or more people they say have been detained, but the scale and goals of the crackdown remain unclear, even to those who fear they could be targeted.