Double Time out of Taos by Baer Charlton

When someone threatens a congressman's family and career, he seeks the FBI's best. They give Special Agent Nash Running Bear no choice.

She scoffs at the babysitting job in the high desert of New Mexico, but it quickly becomes a deadly game of cat and mouse. And the cats are six international assassins. So to get the job done, Nash reaches out to her alphabet team. Hopefully, in time...