ST. LOUIS (AP)- Trustees of the Fireman’s Retirement System of St. Louis are suing to block Mayor Francis Slay’s plan for a pension overhaul.

The St. Louis Post-Dispatch reports that the suit was filed Tuesday, seeking a temporary restraining order and judgment against the mayor’s plan that would close the current fire pension system and replace it with a plan with much less-expensive benefits.

The suit says Slay’s plan would cause “drastic and immediate harm” to the pension system.

Slay’s office says the suit is wasteful and premature.

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