16. In its discretion to provide and maintain a transit police department and a uniformed transit police force. Such department and force shall have the power and it shall be their duty, in and about transit facilities, to preserve the public peace, prevent crime, detect and arrest offenders, suppress riots, mobs and insurrections, disperse unlawful or dangerous assemblages and assemblages which obstruct free passage; protect the rights of persons and property; guard the public health; regulate, direct, control and restrict pedestrian traffic; remove all nuisances; enforce and prevent violation of all laws and ordinances; and for these purposes to arrest all persons guilty of violating any law or ordinance. Appointments to such transit police force shall be made in accordance with applicable provisions of the civil service law and only persons who shall be less than twenty-nine years of age at the date of the filing of an application for civil service examination, who have never been convicted of a felony, and who are citizens of the United States shall be appointed transit patrolmen on the transit police force. Each member of such force shall be a police officer as defined by paragraph (e) of subdivision thirty-four of section 1.20 of the criminal procedure law and shall possess all the powers of a police officer of a city in the execution of criminal process; and criminal process issued by any court or magistrate of a city may be directed to and executed by a member of such force, notwithstanding the provisions of any local or special act, ordinance or regulation. The authority may appoint a chief and a deputy chief of the transit police department who, in the discretion of the authority, may be selected from the ranks of the transit police force, and assign powers and duties to them and fix their compensation. The chief shall be the head of such department. During the absence or disability of the chief, the deputy chief shall possess all the powers and perform all the duties of the chief. The transit police force shall consist of captains, lieutenants, sergeants and police officers. The authority may detail persons in the rank of captain of the transit police force to serve in higher ranks. A captain when so detailed to serve in a higher rank may be granted an increase in salary above the grade established for the rank of captain in the uniformed force. The authority may maintain a division for detective purposes to be known as the detective division and may, from time to time, detail to service in said division as many members of the force as it may deem necessary, and may at any time revoke any such detail. Any member of the force while so detailed may be granted an increase in salary above the grade established for his or her rank in the uniformed force, but shall retain his or her rank in the force and shall be eligible for promotion the same as if serving in the uniformed force, and the time during which he or she serves in such division shall count for all purposes as if served in his or her rank or grade in the uniformed force.