If the police, army, or any group of people in authority move in, or if someone moves them in, they take control or attack, in order to deal with a difficult or dangerous situation.

When a company goes out of business, officials usually move in to take control. 如果公司倒闭，政府官员通常会接手操控局面。

The decision has been made to move UN troops in to try and stop the fighting. 已决定派遣联合国部队进驻该地区以制止这场冲突。