The phrase "a string of police" is not correct and does not convey a clear meaning in written English.
It could be used in a context where you are describing a series of police officers or vehicles, but it is not a common expression.
Example: "As the protest escalated, a string of police arrived to maintain order."
Alternatives: "a line of police" or "a group of police".
Why did a string of police officials resign in the months that followed?
Four years later, a string of police shootings of black people prompted investigators to return in 2010.
(They have also manhandled and arrested reporters).The cause of the conflict is the latest in a string of police killings of unarmed black men across America.
A string of police blunders led to the innocent electrician being held down by police and shot repeatedly in the head.
In the 1980s, a string of police shootings of children prompted Congress to pass the first and only federal regulations on toy guns.
The surge in violence had started in 2005, and a string of police and military operations by his predecessor Vicente Fox had failed to stem the bloodshed.
Defence officials have previously acknowledged that several "red flags" were missed in Alexis's background, allowing him to achieve and retain a secret security clearance and work as a navy contractor despite a string of police-related and behavioral problems.
At news conferences and in pulpits across the city, the mayor's political foes seized on the melee as further evidence of what they described as the mismanagement of a police department that they contended was losing the faith of New Yorkers, especially in minority areas, after a string of police-involved shootings of unarmed men.
Tributes were paid today by a string of policing colleagues and Home Secretary Theresa May, with whom Mr McKeever had heated clashes.
The incident is the latest in a string of controversial police shootings that have once again put law enforcement's use of lethal force, particularly against black men, in the national spotlight.
Yet after a string of fatal police shootings of black men in South Carolina, Missouri and other states, the poll found 43% of California voters think police generally are tougher on blacks than on any other group, up from 33% in September.
