TULSA, Oklahoma - Some instructors at Spartan College of Aeronautics and Technology started a strike Monday over better pay and benefits - mainly the cost of their health care.

A union representative for the instructors said the school offered a contract that included a 35 percent increase in health care premiums and wanted the union to approve it before negotiating salary and other benefits.

After the contract expired in April, the instructors have been working under contract extensions. The union decided Friday to call a strike after not reaching an agreement in talks that ended Thursday.

Spartan spokesperson Sheila Curley said the strike was a surprise to the school, which had, until last Thursday, been in talks they thought were being productive.

She said the health insurance premiums were in line with increases seen in other industries.

Curley said the strike was impacting a few classes at Spartan's two north Tulsa campuses, but not flight training at Jones Riverside Airport.

She said Spartan is considering using instructors from out of state campuses to fill gaps if the strike continues.