1. Any member of the police department of any such city having served faithfully twenty-five years or more in the department, of which the last three years shall be continuous, may make application to be relieved from the department, and in such event or if any such member is removed, suspended or discharged from the department after such tenure of service the board of trustees shall order and direct that the person shall be paid a monthly pension equal to one-half the average monthly rate of salary which the member received on the force during the twelve months immediately preceding the date of his retirement.

2. Any member who remains on active duty in the department and continues to make regular and periodic payments into the pension fund as provided in sections 86.510 to 86.577 for a period of time beyond twenty-five years, shall, upon subsequent retirement, be paid monthly, in addition to the retirement benefit provided in subsection 1 of this section, a sum equal to one percent of the average monthly salary of the member during the twelve months immediately preceding the effective date of his retirement for each full twelve month period beyond twenty-five years but not to exceed ten additional twelve month periods.

3. After the decease of the member, his wife while single, and children under eighteen years of age, if any survive him, shall be entitled to the pension provided for in sections 86.510 to 86.577.